Below-Grade Waterproofing
Neutrality remake campaign: from-scratch field derivation per authoring cheatsheet; project parameters and derived dispositions
Showing changes from Rev 7
to Rev 8
in Below-Grade Waterproofing.
−---
−title: Below-Grade Waterproofing
−category: Building Envelope
−toc_depth: 3
−description: >
− When to use: Waterproofing and dampproofing of below-grade foundation walls and slabs-on-grade or suspended slabs below finished grade for commercial, institutional, and residential buildings. Covers all primary membrane types used in positive-side and blindside/pre-applied configurations: self-adhering modified bituminous sheet, fluid-applied elastomeric, bentonite geosynthetic clay liner, and hot-applied rubberized asphalt. Addresses dampproofing for non-hydrostatic conditions, substrate preparation, protection course, drainage composites and foundation drainage, detailing at penetrations and construction joints, and field testing including flood test and electronic leak detection.
− Not intended for: Plaza deck and parking structure waterproofing over occupied space (see [[sync/membrane-roofing]]); below-slab vapor retarder installed as a standalone vapor control measure without waterproofing (see [[sync/vapor-barriers-under-slab]]); waterproofing of water-containment structures (tanks, reservoirs, pools); concrete integral crystalline waterproofing admixtures (see [[sync/cast-in-place-concrete]]); foundation drainage design without a waterproofing scope (see [[sync/foundation-drainage]]).
−---
−
−# Scope {toc}
−
−## This standard covers the design basis, materials, installation, and field testing of below-grade waterproofing and dampproofing systems applied to foundation walls, basement walls, grade beams, and slabs that retain earth and enclose occupied interior spaces. {note}
−## The system encompasses the primary waterproofing membrane, terminations and transitions, detailing at structural and mechanical penetrations, the protection course, and the drainage composite or drainage aggregate layer that relieves hydrostatic pressure and channels groundwater to the foundation drainage system. {note}
−
−## The single most important decision in below-grade waterproofing is whether hydrostatic pressure will act on the assembly, and that determination drives membrane type, application thickness, drainage requirements, and testing protocol. {note}
−
−### The Engineer of Record shall establish the design groundwater elevation from a site-specific geotechnical investigation.
−
−### Waterproofing system selection that proceeds without a confirmed design groundwater elevation represents a design omission that commonly results in system failure. {note}
−
−### Below-grade waterproofing is a system, not a membrane; a technically correct membrane applied over an improperly prepared substrate, without a protection course, without correctly installed drainage, or without proper detailing at penetrations and terminations will fail. {note}
−
−### Industry failure data consistently show that the membrane itself is rarely the root cause of leakage, and that construction joints, expansion joints, penetrations, and terminations at system edges are the locations where failures concentrate. {note}
−
−### The Contractor shall read this standard in its entirety before beginning installation.
−
−### The Contractor shall require an on-site pre-installation conference to review details before any waterproofing work begins.
−
−### Coordinate the waterproofing scope with [[sync/cast-in-place-concrete]] for concrete substrate quality requirements, with [[sync/earthwork]] for backfill compaction requirements adjacent to waterproofed walls, and with [[sync/foundation-drainage]] for perimeter drain design and outlet requirements.
−
−### Where building thermal insulation is applied to the exterior of below-grade walls, coordinate with [[sync/building-thermal-insulation]] for insulation placement relative to the waterproofing membrane.
−
−# Referenced Standards {toc}
−
−## Materials, testing, and installation shall comply with the current edition of the following standards.
−
−| Standard | Title |
−|----------|-------|
−| IBC Chapter 18 / Section 1805 | Dampproofing and Waterproofing (International Building Code) |
−| ASTM D5385/D5385M | Standard Test Method for Hydrostatic Pressure Resistance of Waterproofing Membranes |
−| ASTM C836/C836M | Standard Specification for High Solids Content, Cold Liquid-Applied Elastomeric Waterproofing Membrane for Use with Separate Wearing Course |
−| ASTM D7832/D7832M | Standard Guide for Performance Attributes of Waterproofing Membranes Applied to Below-Grade Walls / Vertical Surfaces (Enclosing Interior Spaces) |
−| ASTM D7492/D7492M | Standard Guide for Use of Drainage System Media with Waterproofing Systems |
−| ASTM D8425 | Standard Guide for the Use of Sodium Bentonite Needle-Punched Geotextile Waterproofing Systems with Cast-in-Place Concrete Below-Grade Foundation |
−| ASTM D6506/D6506M | Standard Specification for Asphalt-Based Protection Board for Below-Grade Waterproofing |
−| ASTM C898/C898M | Standard Guide for Use of High Solids Content, Cold Liquid-Applied Elastomeric Waterproofing Membrane with Separate Wearing Course |
−| ASTM D1970/D1970M | Standard Specification for Self-Adhering Polymer Modified Bituminous Sheet Materials Used as Steep Roofing Underlayment for Ice Dam Protection |
−| ASTM E1745 | Standard Specification for Plastic Water Vapor Retarders Used in Contact with Soil or Granular Fill under Concrete Slabs |
−| ACI PRC-515.2 | Guide to Selecting Protective Treatments for Concrete |
−| ACI PRC-515.3 | Guide for Assessment and Surface Preparation for Application of Protection Systems for Concrete |
−| ICRI 310.2R | Selecting and Specifying Concrete Surface Preparation for Sealers, Coatings, Polymer Overlays, and Concrete Repair |
−
−## Materials, testing, and installation shall comply with the current edition of the referenced standards.
−
−## Where contract documents or referenced standards conflict, the more stringent requirement governs unless the Engineer of Record directs otherwise in writing.
−
−# Submittals {toc}
−
−## Action Submittals {toc}
−
−### The Contractor shall submit the following for the Engineer's review and approval prior to procurement or installation of any waterproofing materials.
−
−- Manufacturer's product data sheets for each waterproofing membrane, primer, protection board, drainage composite, and accessory sealant, including published application rates, temperature limitations, cure time, and compatibility certifications for adjacent materials
−- Installation instructions for each waterproofing product, including membrane, flashings, transition membranes, pipe boot assemblies, and termination bars
−- Manufacturer's certification that products submitted are compatible with each other and with the concrete or masonry substrate
−- Applicable test reports demonstrating conformance with referenced ASTM standards, specifically hydrostatic pressure resistance per ASTM D5385/D5385M for any system used in hydrostatic pressure conditions
−- Membrane thickness confirmation plan, including proposed wet-film thickness for fluid-applied membranes and minimum finished dry-film thickness
−- Pre-installation conference agenda and proposed attendees list, submitted at least 10 days before the pre-installation conference
−- Qualifications documentation for the waterproofing installer
−
−```datasheet
−label: Action Submittals Required
−type: checkbox
−options:
− - "Product data for membrane, primer, and accessories"
− - "Installation instructions for membrane system"
− - "Manufacturer compatibility certification for all products"
− - "Hydrostatic pressure resistance test report (ASTM D5385/D5385M)"
− - "Membrane thickness confirmation plan"
− - "Pre-installation conference agenda"
− - "Installer qualifications"
−default: "Product data for membrane, primer, and accessories"
−```
−
−### The Contractor shall submit the action submittal items listed above for the Engineer's review and approval prior to procurement or installation of any waterproofing materials.
−
−### No portion of the waterproofing installation shall proceed until the corresponding submittals have been reviewed and returned.
−
−## Closeout Submittals {toc}
−
−### The Contractor shall provide the following at substantial completion before the waterproofing system is accepted.
−
−- Manufacturer's written warranty for waterproofing materials, countersigned by the Contractor, running to the Owner
−- Installer's written warranty running to the Owner for workmanship and watertightness
−- Flood test reports or electronic leak detection reports, signed by the testing technician, for all tested areas
−- Documented record of areas repaired after testing, including repair location, repair method, and re-test result
−- As-installed sketch showing locations of all laps, seams, transitions, penetration flashings, and any areas where deviations from the approved installation plan occurred
−
−```datasheet
−label: Closeout Submittals Required
−type: checkbox
−options:
− - "Manufacturer's written warranty, countersigned, running to Owner"
− - "Installer's written warranty for workmanship and watertightness"
− - "Flood test or electronic leak detection reports, signed by technician"
− - "Documented record of areas repaired after testing"
− - "As-installed sketch of laps, seams, transitions, and penetration flashings"
−default: "Manufacturer's written warranty, countersigned, running to Owner"
−```
−
−### The Contractor shall provide the closeout submittals listed above at substantial completion before the waterproofing system is accepted.
−
−# Quality Assurance {toc}
−
−## Installer Qualifications {toc}
−
−```datasheet
−label: Installer Qualification Basis
−type: radio
−options:
− - "Manufacturer-authorized installer"
− - "Documented experience — minimum 5 completed projects of similar scope"
− - "Manufacturer-authorized and documented experience"
−default: "Manufacturer-authorized installer"
−```
−
−### Below-grade waterproofing shall be performed by an installer experienced in the type of membrane system being installed who can demonstrate a documented history of successful completed projects of similar scope and complexity.
−
−### For fluid-applied systems, the installer shall be authorized or trained by the membrane manufacturer.
−
−### For blindside and pre-applied systems, the installer shall be able to demonstrate familiarity with the sequencing constraints of the system and with the requirements for concrete placement against pre-applied membranes.
−
−## Pre-Installation Conference {toc}
−
−### A pre-installation conference shall include the Owner's Representative or Engineer, the General Contractor, the waterproofing subcontractor, and a manufacturer's technical representative.
−### Topics shall include substrate acceptance criteria, required concrete cure time before membrane application, temperature and weather constraints, sequencing with other trades, lap and seam requirements, protection course installation, backfill timing and compaction requirements, testing plan, and responsibilities for inspection and repair.
−
−### A pre-installation conference shall be held on-site before any waterproofing installation begins.
−
−### The pre-installation conference shall include the Owner's Representative or Engineer, the General Contractor, the waterproofing subcontractor, and a manufacturer's technical representative.
−
−### Pre-installation conference topics shall include substrate acceptance criteria, required concrete cure time before membrane application, temperature and weather constraints, sequencing with other trades, lap and seam requirements, protection course installation, backfill timing and compaction requirements, testing plan, and responsibilities for inspection and repair.
−
−### Minutes of the pre-installation conference shall be recorded and distributed.
−
−### The pre-installation conference is the single most cost-effective quality step in below-grade waterproofing, because resolving sequencing conflicts, substrate questions, and detail ambiguities before work begins consistently reduces remedial work and claims. {note}
−
−### Requiring the manufacturer's technical representative — not just a distributor — to attend ensures that application requirements are confirmed for the specific products being used on this project. {note}
−
−## Manufacturer Technical Representative {toc}
−
−### The membrane manufacturer shall provide a technical representative to inspect the substrate before installation begins, to observe the first day of installation, and to be available by phone or on-site for any issues that arise during installation.
−
−### The technical representative shall confirm in writing that the substrate conditions, application method, and environmental conditions on the day of first installation observation meet the manufacturer's requirements.
−
−## Regulatory Inspection {toc}
−
−### All below-grade waterproofing shall be available for inspection by the Authority Having Jurisdiction before being covered by protection course, drainage composite, insulation, or backfill.
−
−### The Contractor shall coordinate inspection timing and shall schedule the waterproofing inspection and the Owner's quality observation before any concealing work proceeds.
−
−# Design Basis — Hydrostatic vs. Non-Hydrostatic {toc}
−
−## The distinction between hydrostatic and non-hydrostatic conditions is the governing design basis for the entire waterproofing system. {note}
−## Hydrostatic pressure acts whenever groundwater stands in contact with the assembly. {note}
−## Even a "seasonally high" water table — groundwater that rises only during spring thaw or prolonged rain — is a hydrostatic condition during those periods. {note}
−
−## IBC Section 1805 requires that where a subsurface soil investigation indicates a hydrostatic pressure condition exists, walls shall be waterproofed with a system capable of resisting hydrostatic pressure.
−
−## Where hydrostatic pressure will not occur as determined by IBC Section 1803.5.4, dampproofing is the minimum requirement.
−
−## The design basis shall be explicitly documented in the contract documents so that the membrane type selection is traceable to a geotechnical basis.
−
−```datasheet
−label: Design Groundwater Condition
−type: radio
−options:
− - "Non-hydrostatic — groundwater table is at least 6 ft below lowest slab, confirmed by geotechnical investigation"
− - "Intermittently hydrostatic — seasonal high water table reaches below-grade assembly, confirmed by geotechnical investigation"
− - "Continuously hydrostatic — groundwater table is at or above the lowest slab elevation, confirmed by geotechnical investigation"
−drawing_ref: true
−default: "Non-hydrostatic — groundwater table is at least 6 ft below lowest slab, confirmed by geotechnical investigation"
−```
−
−## An assembly sized only for non-hydrostatic conditions will fail under seasonal hydrostatic loading. {note}
−
−## The geotechnical engineer's report shall establish both the normal groundwater elevation and the expected seasonal high water table elevation.
−
−```datasheet
−label: Design Groundwater Elevation
−type: text
−drawing_ref: "geotechnical report"
−default: deferred
−```
−
−```datasheet
−label: Geotechnical Report Reference
−type: text
−default: "Boring logs and groundwater data from geotechnical investigation report per soils engineer of record"
−```
−
−## Where the design groundwater condition is intermittently or continuously hydrostatic, the waterproofing membrane shall be capable of resisting the design hydrostatic head confirmed by the geotechnical investigation.
−
−## IBC Section 1805.3 requires that waterproofing be applied from the bottom of the wall or slab to not less than 12 in. above the maximum elevation of the design groundwater table.
−
−```datasheet
−label: Waterproofing Application Extent — Walls
−type: select
−options:
− - "Full height — slab bottom to finished grade (recommended where water table is within 6 ft of lowest slab)"
− - "Partial — slab bottom to 12 in. above design high-water-table elevation, remainder dampproofed per IBC 1805.2.2"
− - "Dampproofing only — non-hydrostatic condition, confirmed by geotechnical investigation"
−drawing_ref: true
−default: "Full height — slab bottom to finished grade (recommended where water table is within 6 ft of lowest slab)"
−```
−
−## The remainder of the wall above the waterproofed elevation shall be dampproofed per Section 1805.2.2.
−
−## Where the groundwater table is within 6 ft of the lowest slab, a full waterproofing system from slab bottom to finished grade elevation is generally the most defensible and cost-effective approach, because relying on a mid-wall transition from waterproofing to dampproofing introduces a seam detail that is a common leak source. {note}
−
−# Dampproofing {toc}
−
−## Applicability {toc}
−
−### Dampproofing is the minimum treatment required by IBC Section 1805.2 for walls and slabs that retain earth and enclose interior spaces where hydrostatic pressure will not occur. {note}
−### Dampproofing controls soil moisture and capillary moisture migration but is not designed to resist hydrostatic pressure. {note}
−
−### The use of dampproofing as the sole moisture control measure shall be restricted to confirmed non-hydrostatic conditions based on a geotechnical investigation.
−
−### Dampproofing on a below-grade assembly that is subject to any hydrostatic loading, even intermittently, will fail. {note}
−
−## Dampproofing Materials {toc}
−
−```datasheet
−label: Dampproofing Material Type
−type: radio
−options:
− - "Bituminous coating — cold-applied emulsified asphalt"
− - "Cementitious polymer-modified coating"
− - "Single-ply self-adhering modified bituminous sheet, minimum 30-mil total thickness"
− - "Not applicable — full waterproofing system specified"
−default: "Bituminous coating — cold-applied emulsified asphalt"
−```
−
−```datasheet
−label: Dampproofing — Portland Cement Parging Required (masonry walls only)
−type: radio
−options:
− - "Yes — masonry substrate requires 3/8-in. parging coat before dampproofing"
− - "No — concrete substrate, parging not required"
−default: "No — concrete substrate, parging not required"
−```
−
−### For concrete walls, dampproofing shall consist of a bituminous coating, a cementitious parging, or an approved synthetic dampproofing compound applied to the exterior face of the foundation wall, from the top of the footing to finished grade.
−
−### For masonry walls, a minimum 3/8-in.-thick portland cement parging shall be applied to the exterior face, followed by a bituminous coating.
−
−### The parging shall be full-coverage, thoroughly troweled, and free of voids before the bituminous dampproofing coat is applied.
−
−### For slabs-on-grade that are dampproofed rather than waterproofed, a 4-in.-minimum granular drainage layer of clean, open-graded aggregate beneath the slab shall be provided and shall be tied into the perimeter drainage system.
−
−### The dampproofing slab condition does not eliminate the need for a sub-slab vapor retarder where the slab supports flooring materials sensitive to moisture vapor transmission; coordinate with [[sync/vapor-barriers-under-slab]].
−
−# Waterproofing Materials {toc}
−
−## System Selection {toc}
−
−### Four primary below-grade waterproofing system types are addressed by this standard. {note}
−### The selection shall be based on the hydrostatic condition, substrate geometry and accessibility, construction sequence constraints, and project-specific compatibility requirements.
−
−```datasheet
−label: Primary Waterproofing Membrane System
−type: radio
−options:
− - "Self-adhering modified bituminous sheet — positive side, post-applied"
− - "Fluid-applied cold liquid elastomeric — positive side, post-applied"
− - "Bentonite geosynthetic clay liner (GCL) — positive side or blindside"
− - "Pre-applied (blindside) modified bituminous sheet — applied before concrete placement"
− - "Hot-applied rubberized asphalt — positive side, post-applied"
−default: "Self-adhering modified bituminous sheet — positive side, post-applied"
−```
−
−### The waterproofing system selection shall be based on the hydrostatic condition, substrate geometry and accessibility, construction sequence constraints, and project-specific compatibility requirements.
−
−### Where blindside construction is required — such as at a property-line wall, a retained excavation, or a pile-supported mat — only a pre-applied membrane is appropriate because positive-side access is not available after concrete is placed.
−
−## Self-Adhering Modified Bituminous Sheet Membrane {toc}
−
−### Self-adhering modified bituminous sheet membranes for below-grade use are composed of SBS (styrene-butadiene-styrene) or APP (atactic polypropylene) polymer-modified bitumen laminated to a carrier film or reinforcing fabric, with a release film protecting a self-adhering pressure-sensitive adhesive on the face applied to the substrate. {note}
−### The finished assembly provides a continuous sheet membrane that bonds directly to the prepared concrete or masonry substrate without heat, eliminating open-flame torch application in an occupied or confined work area. {note}
−
−### The minimum thickness of self-adhering sheet membrane at walls shall be specified based on whether the wall condition is hydrostatic or non-hydrostatic.
−
−```datasheet
−label: Self-Adhering Sheet Membrane — Minimum Thickness, Walls
−type: select
−unit: mil
−options:
− - "40 mil (non-hydrostatic only)"
− - "60 mil (hydrostatic and non-hydrostatic)"
−default: "60 mil (hydrostatic and non-hydrostatic)"
−```
−
−### Minimum membrane thickness for vertical walls in hydrostatic applications shall be 60 mil total thickness.
−
−### For non-hydrostatic applications, a minimum 40-mil sheet is acceptable for walls.
−
−### For underslab applications, a minimum 40-mil sheet is acceptable in non-hydrostatic conditions and 60 mil in hydrostatic conditions.
−
−```datasheet
−label: Self-Adhering Sheet Membrane — Minimum Thickness, Underslab
−type: select
−unit: mil
−options:
− - "40 mil (non-hydrostatic only)"
− - "60 mil (hydrostatic and recommended for all underslab)"
−default: "60 mil (hydrostatic and recommended for all underslab)"
−```
−
−### The manufacturer's published minimum thickness requirements for the specific application and hydrostatic head shall always govern where they are more stringent.
−
−### Laps shall be a minimum 3-in. side lap and a minimum 6-in. end lap for sheet membranes.
−
−```datasheet
−label: Sheet Membrane Lap Width — Side Lap (minimum)
−type: select
−unit: in
−options:
− - "3 in."
− - "4 in."
− - "6 in."
−default: "3 in."
−```
−
−```datasheet
−label: Sheet Membrane Lap Width — End Lap (minimum)
−type: select
−unit: in
−options:
− - "6 in."
− - "9 in."
− - "12 in."
−default: "6 in."
−```
−
−### Laps shall be firmly rolled with a minimum 50-lb weighted roller to consolidate the adhesive.
−
−### At inside corners, the membrane shall be reinforced with a 12-in.-wide strip of self-adhering sheet centered on the corner, fully adhered to both faces, before the field membrane is applied.
−
−### At outside corners, the field membrane shall be cut and wrapped continuously, and fish-mouth voids at outside corners shall be cut, lapped, and sealed with a compatible sealant.
−
−## Fluid-Applied Cold Liquid Elastomeric Membrane {toc}
−
−### A fluid-applied membrane is inherently seamless, which eliminates the lap detail risk that exists in sheet membrane systems. {note}
−### However, fluid-applied systems require careful quality control over applied thickness, because a membrane that is applied too thin will fail under hydrostatic pressure, and thickness cannot be verified by eye. {note}
−
−### The minimum dry-film thickness of the fluid-applied membrane on walls shall be specified based on the hydrostatic head and traffic exposure the wall will experience.
−
−```datasheet
−label: Fluid-Applied Membrane — Minimum Dry-Film Thickness, Walls
−type: select
−unit: mil
−options:
− - "60 mil (minimum for hydrostatic applications)"
− - "80 mil (preferred for high-hydrostatic-head applications)"
− - "100 mil (high-hydrostatic-head or traffic-bearing applications)"
−default: "60 mil (minimum for hydrostatic applications)"
−```
−
−### The minimum dry-film thickness of the fluid-applied membrane underslab shall be specified based on the hydrostatic conditions at that location.
−
−```datasheet
−label: Fluid-Applied Membrane — Minimum Dry-Film Thickness, Underslab
−type: select
−unit: mil
−options:
− - "60 mil"
− - "80 mil"
−default: "60 mil"
−```
−
−```datasheet
−label: Fluid-Applied Membrane — Number of Application Coats (minimum)
−type: radio
−options:
− - "2 coats"
− - "3 coats"
−default: "2 coats"
−```
−
−### Fluid-applied cold liquid elastomeric waterproofing conforming to ASTM C836/C836M shall be used where complex substrate geometry, re-entrant corners, numerous penetrations, or other conditions make sheet membrane installation impractical.
−
−### Fluid-applied membranes shall be applied in a minimum two-coat system to the wet-film thickness required to achieve the specified dry-film thickness.
−
−### Each coat shall be applied in a direction perpendicular to the previous coat to ensure uniform coverage.
−
−### The final dry-film thickness shall be verified by the installer using a wet-film gauge during application and by the manufacturer's technical representative during the site visit.
−
−### The fluid-applied membrane shall be continuous from below the bottom of the slab or footing, up the wall, to the specified termination height.
−
−### The fluid-applied membrane shall be cured to the minimum time specified by the manufacturer before applying protection board, insulation, or backfill.
−
−### Minimum cure time is commonly 24 hours but shall be verified from the manufacturer's product data for the ambient temperature and humidity on-site.
−
−### Application below 40°F or above 95°F shall not proceed without specific manufacturer guidance and the Engineer's written approval.
−
−## Bentonite Geosynthetic Clay Liner {toc}
−
−### Sodium bentonite geosynthetic clay liner (GCL) waterproofing systems consist of bentonite clay — typically oven-dried sodium bentonite granules — uniformly distributed between two geotextile layers and needle-punched together. {note}
−### When the bentonite hydrates in contact with water, it swells to form a low-permeability gel layer. {note}
−### Bentonite systems are appropriate for both positive-side and blindside applications and are compatible with the full range of below-grade substrate types. {note}
−### They are particularly useful in blindside configurations because they can be installed on the retained earth face of an excavation or lagging wall before the permanent concrete foundation is cast against them, and they do not require a primer or prepared concrete substrate. {note}
−
−### Bentonite GCL systems conforming to ASTM D8425 shall be lapped a minimum of 12 in. at all seams.
−
−```datasheet
−label: Bentonite GCL Minimum Seam Lap
−type: select
−unit: in
−options:
− - "12 in."
− - "18 in."
−default: "12 in."
−```
−
−### Bentonite GCL systems shall have additional bentonite granules or bentonite strip sealer applied to all laps to ensure continuity of the clay layer through the seam.
−
−### At all edges, terminations, and penetrations, bentonite paste or a compatible sealant shall be applied to seal the edge of the GCL and prevent premature hydration from construction water before backfill.
−
−### Bentonite hydrated with saline water, high-mineral-content groundwater, or water with significant calcium or magnesium content will not swell to the same degree as bentonite hydrated with clean water, and the resulting membrane permeability may be higher than the design value. {note}
−
−### Where groundwater chemistry is unusual or where the soil contains significant concentrations of calcium-based materials such as cement, lime, or fly ash, the geotechnical engineer shall evaluate the compatibility of the groundwater with sodium bentonite.
−
−```datasheet
−label: Bentonite GCL — Groundwater Chemistry Review Required
−type: radio
−options:
− - "Yes — geotechnical engineer to confirm bentonite compatibility with site groundwater"
− - "No — standard freshwater groundwater conditions confirmed by geotechnical investigation"
−default: "Yes — geotechnical engineer to confirm bentonite compatibility with site groundwater"
−```
−
−### Bentonite membranes shall be held in place by the concrete or backfill before they become wet, because a GCL panel exposed to rain or standing water before the concrete is cast against it may swell, shift, or lose bentonite from cut edges, compromising continuity.
−
−### The Contractor shall schedule GCL installation to minimize the open time before coverage.
−
−## Pre-Applied (Blindside) Membrane {toc}
−
−### Pre-applied or blindside waterproofing membranes are installed before the permanent concrete structure is cast, adhering to the outside face of the formwork, lagging, or mud mat. {note}
−### When concrete is placed against the membrane, the membrane bonds to the concrete, resulting in a fully bonded system in which any moisture that migrates through a breach cannot travel laterally between the membrane and the concrete. {note}
−### This lateral-migration resistance is the primary advantage of bonded blindside systems over sheet membranes that rely on pressure contact alone. {note}
−
−### Whether a lean concrete mud mat is required beneath the pre-applied membrane for horizontal underslab application, and its minimum thickness, shall be specified.
−
−```datasheet
−label: Pre-Applied Membrane — Mud Mat Required Under Membrane for Horizontal Underslab Application
−type: radio
−options:
− - "Yes — minimum 2-in. lean concrete mud mat required as uniform substrate"
− - "Yes — minimum 4-in. lean concrete mud mat required"
− - "No — compacted granular fill substrate accepted per geotechnical engineer"
−default: "Yes — minimum 2-in. lean concrete mud mat required as uniform substrate"
−```
−
−### Blindside membranes shall be installed with the adhesive or concrete-bonding face facing the concrete and the waterproofing face facing outward toward the retained earth.
−
−### Sheets shall be lapped per the manufacturer's requirements, typically a minimum of 4 in. at side laps.
−
−```datasheet
−label: Pre-Applied Membrane — Minimum Lap Width
−type: select
−unit: in
−options:
− - "3 in."
− - "4 in."
− - "6 in."
−default: "4 in."
−```
−
−### At inside corners and horizontal-to-vertical transitions, the manufacturer's transition reinforcement membrane and sealant shall be installed as shown on the detail drawings.
−
−### Horizontal to vertical transitions at the wall-slab joint are among the highest-risk details in blindside applications and shall be detailed explicitly on the contract drawings, not addressed by general notes.
−
−## Hot-Applied Rubberized Asphalt {toc}
−
−### Hot-applied rubberized asphalt (HARA) systems are applied as a molten liquid at temperatures above 375°F using heated kettles, yielding a seamless, self-healing membrane with high elongation and excellent crack-bridging properties. {note}
−### Because the material is applied hot and flows into irregular surface conditions and re-entrant angles, it is particularly well-suited to complex below-grade geometry and to substrates with minor surface irregularities. {note}
−### The application requires trained personnel and safety controls for working with hot materials. {note}
−
−### Hot-applied rubberized asphalt shall be applied to the minimum thickness recommended by the manufacturer for the design hydrostatic head.
−
−```datasheet
−label: Hot-Applied Rubberized Asphalt — Minimum Applied Thickness
−type: select
−unit: mil
−options:
− - "90 mil"
− - "120 mil"
− - "180 mil (high hydrostatic head or split-slab condition)"
−default: "90 mil"
−```
−
−### A reinforcing fabric may be embedded in the hot material at inside and outside corners, at construction joints, and at penetrations for additional bridging capacity.
−
−### Protection board shall be installed before the membrane cools to avoid damage from protection board application.
−
−# Substrate Preparation {toc}
−
−## A membrane applied to a poorly prepared substrate will delaminate, bridge over substrate defects, or puncture, regardless of the membrane's own material quality. {note}
−
−## Substrate preparation is the single most cost-effective quality investment in below-grade waterproofing. {note}
−
−## All waterproofing surfaces shall be structurally sound, free of standing water, frost, oil, grease, curing compound not compatible with the membrane, form-release agents, dust, and loose or delaminated material before any primer or membrane is applied.
−
−## The Contractor shall inspect every portion of the substrate before beginning application and shall not apply waterproofing over areas that do not meet the acceptance criteria.
−
−## Concrete Substrate Preparation {toc}
−
−```datasheet
−label: Concrete Substrate — Minimum Age Before Membrane Application
−type: select
−unit: days
−options:
− - "7 days minimum"
− - "14 days minimum (recommended for high-humidity cure or thick sections)"
− - "Per manufacturer's instructions — special formulation for early application"
−default: "7 days minimum"
−```
−
−```datasheet
−label: Concrete Substrate — Surface Moisture Condition
−type: radio
−options:
− - "Dry — no visible moisture, meets manufacturer's maximum moisture content requirement"
− - "Surface dry acceptable — membrane manufacturer has confirmed acceptability of surface-saturated substrate"
−default: "Dry — no visible moisture, meets manufacturer's maximum moisture content requirement"
−```
−
−```datasheet
−label: Inside Corner Treatment Before Membrane
−type: radio
−options:
− - "45-degree coved fillet of non-shrink grout, minimum 3/4-in. leg each face"
− - "Cant strip of compatible rigid foam or prefabricated cant"
− - "Per manufacturer detail — coved membrane reinforcement strip"
−default: "45-degree coved fillet of non-shrink grout, minimum 3/4-in. leg each face"
−```
−
−### New concrete shall reach a minimum age of 7 days and a compressive strength of 2,000 psi before waterproofing is applied, unless the membrane manufacturer's data specifically permits application at an earlier age.
−
−### Concrete surface moisture shall be within the maximum allowed by the membrane manufacturer, tested using a plastic sheet test per applicable method or a surface moisture meter calibrated to the substrate.
−
−### Concrete that is visibly wet from rain, condensation, or curing water shall not be waterproofed until it has dried to the required moisture content.
−
−### Concrete surface profile (CSP) shall conform to ICRI 310.2R.
−
−### For fluid-applied membranes, a minimum CSP of 2 (smooth formed or mechanically floated) is typically required; for self-adhering sheet membranes, a minimum CSP of 1 to 3 is acceptable.
−
−### The manufacturer's primer system shall be used where the substrate is porous, where CSP is in the lower acceptable range, or where indicated by the manufacturer's product data.
−
−### Form ties shall be removed and the cone holes filled with non-shrink grout or a compatible hydraulic cement plug, flush with the wall surface, before applying the membrane.
−
−### Honeycombs and voids greater than 1/4 in. in depth shall be chipped out to sound concrete, cleaned with compressed air, and patched with non-shrink grout before the membrane is applied.
−
−### The membrane shall not be used to bridge over unrepaired honeycombs.
−
−### Concrete fins, ridges, and projections greater than 3/16 in. above the substrate face shall be ground flush.
−
−### Sharp edges and re-entrant corners shall be coved or chamfered with a filler compatible with the membrane system; a 45-degree fillet of non-shrink grout or compatible sealant at inside corners provides the cove required for self-adhering sheet and fluid-applied membranes.
−
−### Concrete projections at form tie locations, bolt holes, and insert holes shall be ground flush.
−
−## Masonry Substrate Preparation {toc}
−
−### Masonry walls to receive waterproofing shall be parged with a minimum 3/8-in.-thick portland cement mortar parging coat, applied by trowel and finished to a smooth, even surface.
−
−### The parging shall be damp-cured for a minimum of 3 days before waterproofing is applied.
−
−### Mortar joints shall be struck flush, and recessed or raked joints that create ridges in the membrane shall be filled with mortar before parging.
−
−## Primer Application {toc}
−
−```datasheet
−label: Primer Required
−type: radio
−options:
− - "Yes — manufacturer's primer required for this substrate condition"
− - "No — self-adhering membrane may be applied without primer per manufacturer data for this substrate"
−default: "Yes — manufacturer's primer required for this substrate condition"
−```
−
−### Primers shall be applied per the membrane manufacturer's instructions, at the rate specified in the product data, and shall be dry or tack-free (as required by the membrane type) before the membrane is applied.
−
−### Primer shall not be applied to standing water or to surfaces below the minimum application temperature.
−
−### Over-application of primer can leave a liquid film that reduces adhesion rather than improving it. {note}
−
−### The Contractor shall verify the correct primer application rate with the technical representative.
−
−# Environmental Conditions {toc}
−
−## For most self-adhering and fluid-applied membranes, the minimum installation temperature is 40°F; for some high-performance fluid-applied systems, the minimum may be lower.
−## Cold weather slows adhesive cure, increases viscosity of fluid-applied products, and reduces adhesion of lap seams. {note}
−
−## The membrane shall not be applied when the ambient air temperature or surface temperature is below the minimum installation temperature specified by the manufacturer.
−
−```datasheet
−label: Minimum Application Temperature — Air and Surface
−type: select
−unit: °F
−options:
− - "40°F (typical manufacturer minimum for self-adhering and most fluid-applied systems)"
− - "25°F with cold-weather formulation (per manufacturer cold-weather data)"
− - "50°F (some water-based fluid-applied systems require higher minimum)"
−default: "40°F (typical manufacturer minimum for self-adhering and most fluid-applied systems)"
−```
−
−## Application below the published minimum temperature without the manufacturer's specific cold-weather application guidance shall not be permitted.
−
−## The membrane shall not be applied when wind conditions will cause premature skinning of fluid-applied products, blow debris onto the uncured membrane, or make sheet lap control impractical.
−
−## The substrate and ambient air shall be at least 5°F above the dew point to prevent condensation on the substrate before and during application.
−
−```datasheet
−label: Minimum Surface Temperature Above Dew Point
−type: select
−unit: °F
−options:
− - "5°F above dew point"
− - "10°F above dew point"
−default: "5°F above dew point"
−```
−
−# Application Sequence {toc}
−
−## Waterproofing shall be applied in a sequence that ensures continuity without skipping areas.
−
−## For walls, application shall begin at the bottom of the wall and work upward so that each sheet course laps over the top of the course below in a shingle pattern oriented to shed any water that migrates through the lap zone downward, not into the building.
−
−## For underslab membranes, application shall proceed from the interior toward the perimeter so that the field laps shed water away from the building interior.
−
−## The wall-to-slab or wall-to-footing transition shall be reinforced in all cases with a 12-in.-wide strip of self-adhering membrane or a trowel-applied sealant fillet before the field membrane is applied, regardless of whether the system is otherwise a fluid-applied or sheet system.
−
−## The sequence shall ensure that the wall membrane and the slab membrane are physically lapped and bonded together at the wall-to-slab joint with no gap.
−
−## The termination of the joint reinforcement strip shall not become a termination that is exposed to water.
−
−# Membrane Laps and Continuity {toc}
−
−```datasheet
−label: End Lap Stagger Between Adjacent Courses (minimum)
−type: select
−unit: in
−options:
− - "12 in."
− - "24 in."
− - "36 in."
−default: "24 in."
−```
−
−## All laps shall be consolidated immediately after application using a weighted roller or by hand pressure per the manufacturer's instructions.
−
−## Laps shall be rolled from the center outward to avoid trapping air.
−
−## Bubbles, wrinkles, and fish-mouths in sheet membrane laps shall be slit, pressed flat, sealed with a compatible sealant, and re-rolled.
−
−## Any lap area that cannot be made fully consolidated and flat shall be lapped over with a minimum 6-in.-wide patch of membrane overlapping all four sides of the defect.
−
−## End laps shall be staggered a minimum of 24 in. between adjacent courses to avoid a continuous vertical line of seams that concentrates stress and leak risk.
−
−# Curing and Protection {toc}
−
−## Membrane exposed to extended UV radiation, foot traffic, or other trades' work without protection is vulnerable to damage. {note}
−
−## No portion of the installed membrane shall be left uncovered at the end of each workday during construction.
−
−## At minimum, protection board shall be applied before any significant construction activity proceeds in the waterproofed area.
−
−## For fluid-applied systems, the membrane shall cure to a minimum hardness per the manufacturer's cure schedule before protection board is applied.
−
−# Detailing at Penetrations and Terminations {toc}
−
−## General Approach {toc}
−
−### Penetrations and terminations are the locations where the majority of below-grade waterproofing failures occur. {note}
−### This is not an incidental observation; it is a consistent finding in industry failure investigations, and it means that the quality of details at these locations — not the field membrane itself — determines whether a below-grade waterproofing system performs. {note}
−
−### Every penetration and termination shall be detailed on the contract drawings before construction begins.
−
−### "See manufacturer's standard details" is not an acceptable substitute for project-specific penetration and termination drawings, because the location, size, and geometric relationship of every penetration to the adjacent membrane system must be resolved before work begins.
−
−## Penetrations — Pipes and Conduits {toc}
−
−```datasheet
−label: Pipe Penetration Treatment — Vertical Wall
−type: radio
−options:
− - "Flexible pre-formed pipe boot — adhered to membrane, sealed to pipe"
− - "Trowel-applied sealant collar with membrane reinforcement strip"
− - "Sheet membrane cut-and-patch with compatible sealant bead at pipe surface"
−default: "Flexible pre-formed pipe boot — adhered to membrane, sealed to pipe"
−```
−
−```datasheet
−label: Pipe Penetration Treatment — Underslab (Horizontal)
−type: radio
−options:
− - "Flexible pre-formed pipe boot, sealed and lapped with underslab membrane"
− - "Sheet membrane collar with trowel-applied sealant at pipe surface"
− - "Pre-formed collar with waterstop at slab-pipe interface"
−default: "Flexible pre-formed pipe boot, sealed and lapped with underslab membrane"
−```
−
−### Each pipe, conduit, sleeve, or structural element passing through a waterproofed wall or slab shall be treated with a continuous, bonded waterproofing detail.
−
−### For positive-side membranes, the membrane shall be applied in a continuous bead or flashing collar around the penetrating element, lapped with the field membrane, and sealed at the interface between the membrane collar and the penetrating element with a compatible sealant or pre-formed boot.
−
−### The sealant shall be applied to a clean, dry, primed surface and shall be tooled to eliminate voids.
−
−### Where the penetrating element moves relative to the structure due to thermal expansion, differential settlement, or vibration, the sealant collar or boot shall be of a flexible material that can accommodate movement without tearing or debonding.
−
−### Rigid cementitious seals shall not be used as the primary seal at pipe penetrations in locations subject to differential movement.
−
−### The Contractor shall minimize the number of penetrations through below-grade waterproofed slabs and walls in hydrostatic conditions.
−
−## Construction Joints {toc}
−
−### Construction joints in concrete — including wall cold joints, horizontal pour joints, and wall-to-slab joints — are the most common leak path in below-grade concrete structures. {note}
−
−### The waterstop type at each below-grade construction joint shall be specified based on the hydrostatic-head condition at that joint.
−
−```datasheet
−label: Waterstop Type at Construction Joints
−type: radio
−options:
− - "PVC waterstop — ribbed or dumbbell profile, minimum 6-in. width in hydrostatic conditions"
− - "Swelling (hydrophilic) waterstop — bentonite or polyurethane type"
− - "Combination — PVC center stop with swelling overlay strip"
− - "Injection tube system — groutable hose installed at joint for post-construction injection if leakage occurs"
−default: "PVC waterstop — ribbed or dumbbell profile, minimum 6-in. width in hydrostatic conditions"
−```
−
−### The minimum waterstop width at wall construction joints shall be specified based on the hydrostatic-head condition at each joint.
−
−```datasheet
−label: Waterstop Width at Wall Construction Joints (minimum)
−type: select
−unit: in
−options:
− - "4 in. (non-hydrostatic conditions)"
− - "6 in. (hydrostatic conditions)"
− - "9 in. (high-hydrostatic-head conditions)"
−default: "6 in. (hydrostatic conditions)"
−```
−
−### Construction joints in below-grade concrete shall be addressed with both a waterstop within the concrete and waterproofing continuity across the joint on the outside face.
−
−### Waterstops shall be installed in construction joints in below-grade concrete before the first concrete pour.
−
−### Waterstops shall be continuous through all reinforcement and shall be lapped and spliced per the manufacturer's instructions, with corner and tee fittings at directional changes rather than field-cut notched joints.
−
−### Field-notched waterstops at corners leave a gap in the waterstop at the most geometrically complex locations. {note}
−
−### On the exterior face, the waterproofing membrane shall be applied continuously across the construction joint.
−
−### For fluid-applied systems, additional material shall be applied over the joint zone to increase local thickness.
−
−### For sheet systems, a reinforcement strip of self-adhering sheet shall be centered on the joint and fully adhered before the field membrane is applied.
−
−### The combination of an interior waterstop and an exterior waterproofing membrane at every construction joint represents the redundant protection that below-grade conditions require. {note}
−
−## Expansion Joints {toc}
−
−```datasheet
−label: Expansion Joint Waterproofing Detail
−type: radio
−options:
− - "Pre-formed flexible expansion joint cover — bonded both sides, freely floating at joint"
− - "Wide-faced composite transition membrane — bonded both sides, centered on joint"
− - "Fluid-applied membrane with expanded reinforcing mesh centered on joint"
−default: "Pre-formed flexible expansion joint cover — bonded both sides, freely floating at joint"
−```
−
−### Expansion joints in below-grade walls and slabs shall be treated with a flexible waterproofing detail that accommodates the design movement without tearing or debonding.
−
−### The design movement at each expansion joint shall be established by the Engineer and shall be communicated to the waterproofing installer so that the correct product and detail geometry can be selected.
−
−### Expansion joint covers and sealants shall be compatible with the adjacent membrane system and shall be installed in accordance with the waterproofing manufacturer's expansion joint detail.
−
−### A fully adhered sheet membrane bridging over an expansion joint without accommodating the joint movement results in membrane tearing at the first thermal cycle. {note}
−
−## Terminations at Grade {toc}
−
−### The termination of the waterproofing system at or above finished grade is the uppermost edge of the system and is a common location for peel-back, delamination, and water entry between the membrane and the substrate. {note}
−
−### The membrane shall be terminated at a height of not less than 8 in. above finished grade in non-hydrostatic conditions, and not less than 12 in. above the design high water table elevation in hydrostatic conditions.
−
−```datasheet
−label: Membrane Termination Height Above Finished Grade (minimum)
−type: select
−unit: in
−options:
− - "8 in. above finished grade (non-hydrostatic)"
− - "12 in. above finished grade (hydrostatic, minimum code per IBC 1805.3)"
− - "18 in. above finished grade (recommended where vegetation or soil splash is a concern)"
−default: "12 in. above finished grade (hydrostatic, minimum code per IBC 1805.3)"
−```
−
−### Terminations shall be mechanically fastened with a termination bar, or embedded in a saw cut, and sealed with a compatible caulk or sealant.
−
−```datasheet
−label: Membrane Termination Method at Grade
−type: radio
−options:
− - "Termination bar — continuous aluminum or plastic bar, mechanically fastened at maximum 8-in. spacing, with sealant at top edge"
− - "Saw cut reglet — membrane embedded in saw cut, wedge-caulked"
− - "Embedded in counter-flashing reglet"
−default: "Termination bar — continuous aluminum or plastic bar, mechanically fastened at maximum 8-in. spacing, with sealant at top edge"
−```
−
−### The membrane shall not be terminated by simply folding the top edge over without mechanical fastening.
−
−## Transition from Positive-Side to Blindside {toc}
−
−### Where a project includes both a positive-side membrane and a blindside pre-applied membrane, the transition detail between the two systems shall be engineered and shown on the drawings.
−
−### The two membrane systems shall be lapped or bonded at the transition so that no gap or unsealed edge exists between them.
−
−### Transition details at positive-side-to-blindside corners shall be resolved in the pre-installation conference before work begins.
−
−# Protection Course {toc}
−
−## Purpose and Requirement {toc}
−
−### The purpose of the protection course is to protect the membrane from mechanical damage during backfill and compaction operations, to shield the membrane from root intrusion in landscaped areas, and to distribute backfill loads rather than concentrating them on the membrane at backfill aggregate contact points. {note}
−
−### A protection course shall be installed over all waterproofing membranes before backfill, concrete placement over underslab membranes, or installation of drainage composites or insulation.
−
−```datasheet
−label: Protection Course Type — Vertical Walls
−type: radio
−options:
− - "Semi-rigid asphalt protection board conforming to ASTM D6506/D6506M, minimum 1/4-in. thick"
− - "Extruded polystyrene rigid insulation board, minimum 1-in. thick (also serves as thermal insulation)"
− - "Composite drainage and protection board (combined protection and drainage function)"
− - "Dimpled drainage composite with protective filter fabric facing"
−default: "Semi-rigid asphalt protection board conforming to ASTM D6506/D6506M, minimum 1/4-in. thick"
−```
−
−```datasheet
−label: Protection Course Type — Underslab
−type: radio
−options:
− - "Semi-rigid asphalt protection board conforming to ASTM D6506/D6506M"
− - "Extruded polystyrene board, minimum 1-in. thick"
− - "Not required — membrane system manufacturer confirms that structural slab can be placed directly on the cured membrane"
−default: "Semi-rigid asphalt protection board conforming to ASTM D6506/D6506M"
−```
−
−### Backfill without a protection course is not permitted.
−
−## Installation Requirements {toc}
−
−### Protection board joints shall be butted tightly and staggered a minimum of 12 in. from adjacent board joints to avoid creating a continuous line through which backfill could concentrate stress on the membrane.
−
−### Protection board shall be fastened to the wall membrane with the manufacturer's specified adhesive or with a compatible adhesive tab system.
−
−### Fasteners that would penetrate the membrane shall not be used to attach protection board.
−
−### At locations where the drainage composite or foundation insulation is installed, the protection board and drainage composite may be combined into a single composite system.
−
−### Coordinate the combined protection-drainage system with the foundation drainage design.
−
−# Foundation Drainage {toc}
−
−## Purpose and Design Basis {toc}
−
−### Foundation drainage is the system of drainage composites and perimeter drains that relieve hydrostatic pressure by channeling groundwater away from the waterproofed assembly before it can build up. {note}
−
−### A waterproofing membrane alone cannot function reliably as the sole moisture management strategy for a below-grade assembly that has continuous or intermittent groundwater contact. {note}
−
−### The combination of a waterproofing membrane and an effective drainage system is the correct design approach for any below-grade assembly subject to hydrostatic conditions.
−
−### Coordinate the drainage design with [[sync/foundation-drainage]].
−
−## Drainage Composite {toc}
−
−### A drainage composite, also known as a drainage board or geocomposite drainage layer, provides a high-transmissivity flow channel between the waterproofed wall or slab and the backfill soil, directing water downward to the perimeter drain. {note}
−
−### The minimum core thickness of the drainage composite shall be specified for use behind the waterproofed wall or slab.
−
−```datasheet
−label: Drainage Composite — Minimum Core Thickness
−type: select
−unit: in
−options:
− - "3/8 in."
− - "5/8 in."
− - "1 in."
−default: "3/8 in."
−```
−
−### The drainage composite shall conform to ASTM D7492/D7492M.
−
−### The drainage composite shall be installed against the protection course on the wall face, from the footing elevation to finished grade, with a filter fabric facing on the soil side to prevent fines migration into the drainage core.
−
−```datasheet
−label: Drainage Composite — Required on Walls
−type: radio
−options:
− - "Yes — drainage composite required on all waterproofed walls in hydrostatic or intermittently hydrostatic conditions"
− - "Yes — drainage composite required on all waterproofed walls regardless of groundwater condition"
− - "No — free-draining granular backfill of sufficient width used in lieu of drainage composite (only in non-hydrostatic conditions)"
−default: "Yes — drainage composite required on all waterproofed walls in hydrostatic or intermittently hydrostatic conditions"
−```
−
−## Perimeter Drain {toc}
−
−```datasheet
−label: Perimeter Drain — Pipe Type
−type: radio
−options:
− - "Perforated PVC pipe, schedule 40, minimum 4-in. diameter, wrapped in filter fabric sock"
− - "Perforated HDPE pipe, minimum 4-in. diameter, wrapped in filter fabric sock"
−drawing_ref: true
−default: "Perforated PVC pipe, schedule 40, minimum 4-in. diameter, wrapped in filter fabric sock"
−```
−
−```datasheet
−label: Perimeter Drain — Minimum Pipe Diameter
−type: select
−unit: in
−drawing_ref: true
−options:
− - "4 in."
− - "6 in."
− - "8 in."
−default: "4 in."
−```
−
−### A perimeter drain shall be installed at the base of the waterproofed wall at or below the bottom of the slab on grade, conveying collected groundwater to daylight, a sump pit, or a storm drainage system.
−
−### The perimeter drain shall be continuous and unobstructed.
−
−### Cleanouts shall be provided at corners and at maximum 100-ft intervals.
−
−### The perimeter drain shall be surrounded by clean, open-graded drainage aggregate — a minimum 6-in.-wide, 12-in.-deep envelope of aggregate conforming to the gradation specified on the drawings — and shall be wrapped in non-woven filter fabric to prevent fines migration.
−
−### The drainage aggregate shall be [[drawing: as indicated on the civil and foundation drawings]].
−
−## Sub-Slab Drainage {toc}
−
−```datasheet
−label: Sub-Slab Drainage Layer — Required
−type: radio
−options:
− - "Yes — minimum 4-in. granular drainage layer, connected to perimeter drain"
− - "Yes — minimum 6-in. granular drainage layer, connected to perimeter drain"
− - "No — non-hydrostatic condition, granular sub-base for structural purposes only"
−default: "Yes — minimum 4-in. granular drainage layer, connected to perimeter drain"
−```
−
−### Where the design hydrostatic condition includes potential for water accumulation under the slab, a granular drainage layer beneath the slab shall be provided.
−
−### For slabs-on-grade in hydrostatic conditions, a minimum 6-in. layer of clean, open-graded granular fill beneath the slab shall be connected to the perimeter drain system.
−
−### The sub-slab granular layer provides both a capillary break and a drainage path. {note}
−
−### The sub-slab drainage system shall be coordinated with the underslab waterproofing membrane placement so that the drainage layer does not compromise the continuity of the membrane.
−
−# Testing and Inspection {toc}
−
−## A waterproofing system cannot be verified by visual inspection alone; testing identifies breaches that are not visible and that would not be found until water entry occurred after backfill and occupation. {note}
−
−## Field testing of installed below-grade waterproofing is mandatory.
−
−## Testing shall be performed before the membrane is covered by the protection course and before backfill begins.
−
−## Flood Test {toc}
−
−```datasheet
−label: Flood Test — Water Head Depth (maximum)
−type: select
−unit: in
−options:
− - "1 in."
− - "2 in."
− - "2 in. maximum (full test area)"
−default: "2 in."
−```
−
−```datasheet
−label: Flood Test — Minimum Duration
−type: select
−unit: hours
−options:
− - "24 hours"
− - "48 hours (recommended for large horizontal areas or where additional confidence is needed)"
−default: "24 hours"
−```
−
−### Flood testing shall be performed on all horizontal waterproofing surfaces — underslab membranes, plaza waterproofing over occupied space, and horizontal membrane transitions.
−
−### A maximum 2-in. head of water shall be ponded on the waterproofed surface for a minimum of 24 hours.
−
−### Before the flood test, the Contractor shall verify that the structure can safely support the dead load of the test water.
−
−### Before the flood test, the Contractor shall install temporary perimeter dams at all edges to contain the water.
−
−### Drains shall be plugged or valved during the flood test.
−
−### Any area of visible moisture penetration through the membrane to the underside shall be marked, the water source removed, the membrane repaired, and the area re-tested.
−
−## Electronic Leak Detection {toc}
−
−### Electronic leak detection (ELD) uses an electrical potential established between an electrically conductive test electrode and the substrate through the membrane; a breach in the membrane allows current to flow and is detected by the scanning electrode. {note}
−### The low-voltage wet method (ASTM D7877) applies a conductive solution to the surface of the membrane and uses a low-voltage (48V or less) electrical potential to locate current flow through breaches. {note}
−### The high-voltage dry method (ASTM D8231) applies a high-voltage pulse to a scanning electrode that is moved across the dry membrane surface and detects voltage discharge through membrane defects. {note}
−
−### The electronic leak detection method shall be specified, or that flood testing serves as the primary test method for this project.
−
−```datasheet
−label: Electronic Leak Detection — Method
−type: radio
−options:
− - "Low-voltage wet method per ASTM D7877 (conductive solution, 48V maximum)"
− - "High-voltage dry method per ASTM D8231"
− - "Both methods — low-voltage for walls, high-voltage dry for horizontal areas"
− - "Not required — flood test is primary test method for this project"
−default: "Low-voltage wet method per ASTM D7877 (conductive solution, 48V maximum)"
−```
−
−### The party responsible for performing electronic leak detection testing, and for reviewing the results, shall be specified.
−
−```datasheet
−label: Electronic Leak Detection — Performed by
−type: radio
−options:
− - "Waterproofing installer — self-testing with results reviewed by Owner's Representative"
− - "Independent third-party testing firm engaged by Owner"
−default: "Independent third-party testing firm engaged by Owner"
−```
−
−### Electronic leak detection (ELD) shall be used on all below-grade vertical wall membranes that will be backfilled, and shall be considered for all horizontal membranes where the flood test cannot be performed due to structural load constraints.
−
−### The low-voltage wet method is the more commonly used method for below-grade vertical membranes, while the high-voltage dry method is commonly used for plaza deck and roofing applications. {note}
−
−### All detected breaches shall be marked, and the Contractor shall repair each breach and re-test the repaired area before the test is considered complete.
−
−### Repairs shall use the same membrane system and shall be applied to a properly prepared, dried surface.
−
−### A patch membrane shall extend a minimum of 6 in. in all directions beyond the breach.
−
−## Visual Inspection Protocol {toc}
−
−### A continuous visual inspection shall be performed by the installer's foreman or the manufacturer's technical representative over the entire installed membrane area, in addition to flood testing and ELD.
−
−### Visual inspection shall confirm membrane continuity, absence of fish-mouths or voids at laps, absence of punctures or tears, minimum coverage at corners and penetrations, proper termination at grade, and condition of all laps.
−
−### Every deficiency found in visual inspection shall be repaired before ELD or flood testing begins.
−
−## Test Reports {toc}
−
−### All flood test and ELD test results shall be recorded on signed test reports that include the test method, date, ambient temperature, the area tested, the instrument identification and calibration date (for ELD), the map of any detected breaches with their locations identified by coordinates or by reference to the as-installed sketch, the repair method used for each breach, and the pass/fail result of the re-test after repair.
−
−### Test reports shall be included in the closeout submittals.
−
−# Backfill {toc}
−
−## Timing {toc}
−
−### Backfill shall not proceed until the membrane has passed all required testing, the protection course is fully installed, and the drainage composite is in place.
−
−### Backfilling before testing is complete eliminates the possibility of locating and repairing breaches without excavation. {note}
−
−## Backfill Material {toc}
−
−```datasheet
−label: Maximum Particle Size in Backfill Within 12 in. of Protection Course
−type: select
−unit: in
−options:
− - "3/4 in."
− - "1-1/2 in."
−default: "3/4 in."
−```
−
−```datasheet
−label: Maximum Backfill Lift Thickness Within 4 ft of Wall
−type: select
−unit: in
−options:
− - "8 in."
− - "12 in."
−default: "8 in."
−```
−
−### Backfill material adjacent to the waterproofed wall shall be free of large rock, debris, frozen clods, or any material with a particle size greater than 3/4 in. within the first 12 in. of fill against the protection course.
−
−### Rock fragments, concrete rubble, and debris shall be excluded from the backfill zone adjacent to the membrane.
−
−### Where drainage composite is installed, the backfill shall be compacted in lifts not to exceed 8 in. using hand-operated equipment within 4 ft of the wall to avoid lateral loads that could damage the drainage composite or push it away from the wall face.
−
−## Compaction {toc}
−
−### Backfill shall be compacted to a minimum 95 percent of standard Proctor density per ASTM D698, or as required by the geotechnical engineer, within the limits shown on the civil drawings.
−
−### Over-compaction of backfill adjacent to a below-grade wall using large vibratory rollers is a structural concern independent of the waterproofing. {note}
−
−### The Contractor shall coordinate compaction equipment selection with the structural engineer's lateral load design basis for the wall.
−
−# Warranty {toc}
−
−## Manufacturer Warranty {toc}
−
−```datasheet
−label: Manufacturer Waterproofing Material Warranty Period (minimum)
−type: select
−unit: years
−options:
− - "5 years"
− - "10 years"
− - "15 years"
− - "20 years"
−default: "10 years"
−```
−
−### The waterproofing membrane manufacturer shall provide a written warranty to the Owner against defects in materials and workmanship for a minimum period of 5 years from the date of substantial completion.
−
−### The manufacturer's warranty shall identify the membrane system, the application location, and the scope of the warranted installation as documented by the test reports and the as-installed sketch.
−
−### For projects where the warranty is project-specific, it shall run to the Owner and be assignable.
−
−## Installer Warranty {toc}
−
−```datasheet
−label: Installer Workmanship Warranty Period (minimum)
−type: select
−unit: years
−options:
− - "1 year"
− - "2 years"
− - "5 years"
−default: "2 years"
−```
−
−### The waterproofing installer shall provide a written warranty to the Owner against defects in workmanship and against water infiltration through the installed system for a minimum of 2 years from the date of substantial completion.
−
−### The installer's warranty shall be in addition to, not in lieu of, the manufacturer's material warranty.
−
−## Exclusions {toc}
−
−### Exclusions for structural failure of the building, changes to groundwater due to adjacent construction, and direct physical damage by subsequent construction activities are customary and acceptable. {note}
−
−### Warranty exclusions shall not include failures caused by installation methods that deviate from the approved submittal, substrate preparation methods, or material applications that do not comply with this specification.
−
−### The Contractor shall review proposed warranty exclusion language with the Owner's legal counsel before execution.
−
−# Common Errors and Risk Areas {toc}
−
−## This section summarizes the conditions and installation practices that most frequently generate RFIs, change orders, warranty claims, and litigation in below-grade waterproofing projects. {note}
−## These are documented patterns from field investigations and peer-reviewed construction failure literature, not theoretical risks. {note}
−
−## Specifying a dampproofing-only system without a geotechnical report confirming non-hydrostatic conditions is the root cause of a large proportion of basement leakage problems in commercial construction; the geotechnical investigation is a required design input, not an optional enhancement. {note}
−
−## The joint where the underslab membrane meets the wall membrane is the geometric point of highest stress and the most common single leak location, and a field-resolved "tie-in" without a contract-drawing detail is a frequent failure point. {note}
−
−## Waterstops that are field-notched or bent without prefabricated corner fittings leave a gap at the corner at every construction joint corner and tee. {note}
−
−## Protection board applied before flood test or ELD is performed makes it impossible to locate and repair breaches without removing the protection board; the correct sequence is membrane, test, repair, re-test, protection board, drainage composite, backfill. {note}
−
−## Moisture under a self-adhering membrane or a fluid-applied coating degrades adhesion and, in severe cases, causes blistering or complete delamination, and is missed when concrete moisture content is judged visually rather than by test. {note}
−
−## Unrolled laps in self-adhering sheet membranes retain the lap zone as an unbonded cavity that groundwater can enter and travel laterally when laps are not rolled immediately after application. {note}
−
−## Sealant-only penetration details are prone to delamination when the pipe moves, whereas pre-formed flexible boots provide movement accommodation that caulk cannot. {note}
−
−## Lime-treated subgrades or cement-stabilized fill in contact with bentonite can prevent hydration, resulting in a GCL that never forms an effective seal when the soil contact chemistry is not reviewed for compatibility. {note}
−
−## A membrane edge that is simply folded over or sealed with sealant alone is vulnerable to peel-back from soil movement, freeze-thaw, and vegetation when the termination is not mechanically fastened with a termination bar. {note}
−
−## Backfilling before flood test and ELD is the single most damaging construction sequencing error in below-grade waterproofing because it converts a correctable deficiency into an excavation-and-reconstruction problem. {note}
+---
+title: Below-Grade Waterproofing
+category: Building Envelope
+description: >
+ When to use: Waterproofing of below-grade walls and slabs that retain earth and enclose interior space, where a groundwater investigation confirms a hydrostatic pressure condition or where the Owner requires waterproofing-level protection regardless of the groundwater finding. Covers the membrane families used below grade (self-adhering modified bituminous sheet, cold fluid-applied elastomeric, hot-applied rubberized asphalt, sodium bentonite geotextile composite, pre-applied bonded sheet, and surface-applied cementitious crystalline coating), positive-side, negative-side, and pre-applied blindside application, substrate preparation and priming, application temperature limits, laps and terminations, detailing at penetrations and joints, the protection course, the drainage layer bearing on the membrane, field watertightness verification, backfill against waterproofed surfaces, and warranties.
+ Not intended for: Dampproofing of walls and slabs where the groundwater investigation confirms no hydrostatic condition (see [[sync/dampproofing]]); perimeter drain, sub-slab drainage, sump, and discharge design (see [[sync/foundation-drainage]]); under-slab vapor retarders installed for vapor control without a waterproofing function (see [[sync/vapor-barriers-under-slab]]); plaza deck and parking structure waterproofing over occupied space (see [[sync/membrane-roofing]]); waterproofing of water-containment structures such as tanks, reservoirs, and pools; integral crystalline or hydrophilic admixtures batched into the concrete mix (see [[sync/cast-in-place-concrete]]); waterstops cast into concrete joints (see [[sync/concrete-joints-and-waterstops]]); and the above-grade air and water-resistive barrier plane (see [[sync/air-barriers]]).
+---
+
+# Scope {toc}
+
+## This standard covers the waterproofing membrane applied to below-grade walls and slabs that retain earth and enclose interior space, together with the substrate preparation beneath it, the terminations and detailing that close its edges and openings, the protection course that shields it, the drainage layer that bears against it, and the field verification that proves it watertight. {note}
+
+## Waterproofing and dampproofing are distinct levels of protection with distinct code triggers. IBC Section 1805.3 requires waterproofing where the groundwater investigation indicates that a hydrostatic pressure condition exists and the design does not include a groundwater control system; IBC Section 1805.2 requires dampproofing where hydrostatic pressure will not occur. Dampproofing resists soil moisture moving by capillary action and vapor diffusion; waterproofing resists liquid water under head. {note}
+
+## The following are outside this standard and are specified elsewhere: {note}
+- Dampproofing of below-grade walls and slabs in non-hydrostatic conditions, specified in [[sync/dampproofing]]
+- Perimeter drain, sub-slab drainage layer, sump, and discharge design, specified in [[sync/foundation-drainage]]
+- Under-slab vapor retarders installed for vapor control rather than waterproofing, specified in [[sync/vapor-barriers-under-slab]]
+- Plaza deck and parking structure waterproofing over occupied space, specified in [[sync/membrane-roofing]]
+- Waterproofing of tanks, reservoirs, pools, and other water-containment structures
+- Crystalline and hydrophilic waterproofing admixtures batched into the concrete mix, specified in [[sync/cast-in-place-concrete]]
+- Waterstops cast into concrete joints, specified in [[sync/concrete-joints-and-waterstops]]
+- The above-grade air barrier and water-resistive barrier plane, specified in [[sync/air-barriers]]
+
+## The Engineer of Record shall establish the design groundwater elevation and the seasonal high groundwater elevation from a site-specific geotechnical investigation before the waterproofing system is selected.
+
+## The waterproofing system shall be selected and detailed for the seasonal high groundwater elevation rather than for the groundwater elevation observed at the time of the investigation.
+
+## An investigation borehole records the water table on the day it was drilled. A system selected for that reading is at its design limit during the spring thaw and during extended rain events, which are the conditions under which below-grade leakage is reported. {note}
+
+## Below-grade waterproofing performs as an assembly. A membrane correctly matched to the design condition still admits water when the substrate is unsound, the protection course is omitted, the drainage layer is absent, or a penetration is left undetailed, and none of those defects are reachable for repair once the excavation is backfilled. {note}
+
+## Reported below-grade leakage concentrates at construction joints, movement joints, penetrations, tie-ins between adjacent membrane types, and terminations at the edges of the system rather than in the membrane field. {note}
+
+## The below-grade waterproofing membrane shall be made continuous with the above-grade water-resistive barrier specified in [[sync/air-barriers]] at the transition above finished grade.
+
+## Responsibility for installing the transition between the below-grade membrane and the above-grade water-resistive barrier shall be assigned to a single trade at the pre-installation conference and recorded in the conference report.
+
+## Concrete substrate quality, joint layout, and form-tie treatment shall comply with [[sync/cast-in-place-concrete]].
+
+## Backfill materials, placement, and compaction adjacent to waterproofed surfaces shall comply with [[sync/earthwork]] as modified by the lift and equipment limits of this standard.
+
+## Where exterior insulation is applied to the below-grade wall, its placement relative to the membrane shall comply with [[sync/building-thermal-insulation]].
+
+# Referenced Standards {toc}
+
+## Materials, testing, and installation shall comply with the latest adopted edition of each of the following unless a specific edition is cited.
+
+## Where referenced standards conflict, the more stringent requirement shall govern unless the Engineer of Record directs otherwise in writing.
+
+| Standard | Title |
+|----------|-------|
+| International Building Code | Section 1805, Dampproofing and Waterproofing |
+| ASTM C836/C836M | High Solids Content, Cold Liquid-Applied Elastomeric Waterproofing Membrane for Use with Separate Wearing Course |
+| ASTM C898/C898M | Use of High Solids Content, Cold Liquid-Applied Elastomeric Waterproofing Membrane with Separate Wearing Course |
+| ASTM D903 | Peel or Stripping Strength of Adhesive Bonds |
+| ASTM D1621 | Compressive Properties of Rigid Cellular Plastics |
+| ASTM D4263 | Indicating Moisture in Concrete by the Plastic Sheet Method |
+| ASTM D4716/D4716M | Determining the In-Plane Flow Rate per Unit Width and Hydraulic Transmissivity of a Geosynthetic Using a Constant Head |
+| ASTM D5295/D5295M | Preparation of Concrete Surfaces for Adhered (Bonded) Membrane Waterproofing Systems |
+| ASTM D5385/D5385M | Hydrostatic Pressure Resistance of Waterproofing Membranes |
+| ASTM D5957 | Flood Testing Horizontal Waterproofing Installations |
+| ASTM D6506/D6506M | Asphalt-Based Protection Board for Below-Grade Waterproofing |
+| ASTM D7832/D7832M | Performance Attributes of Waterproofing Membranes Applied to Below-Grade Walls / Vertical Surfaces (Enclosing Interior Spaces) |
+| ASTM D7877 | Electronic Methods for Detecting and Locating Leaks in Waterproof Membranes |
+| ASTM D8425 | Use of Sodium Bentonite Needle-Punched Geotextile Waterproofing Systems with Cast-in-Place Concrete Below-Grade Foundation Construction |
+| ASTM F1869 | Measuring Moisture Vapor Emission Rate of Concrete Subfloor Using Anhydrous Calcium Chloride |
+| ASTM F2170 | Determining Relative Humidity in Concrete Floor Slabs Using in situ Probes |
+| ACI PRC-515.2 | Selecting Protective Treatments for Concrete |
+| ACI PRC-515.3 | Assessment and Surface Preparation for Application of Protection Systems for Concrete |
+| ICRI 310.2R | Selecting and Specifying Concrete Surface Preparation for Sealers, Coatings, Polymer Overlays, and Concrete Repair |
+
+## ASTM D7832/D7832M establishes performance attributes for membranes on below-grade walls and does not address bentonite systems, membranes beneath slabs on grade, or membranes applied to soil retaining systems; ASTM D8425 covers the bentonite geotextile family, including application against support of excavation and beneath pressure slabs. {note}
+
+# Submittals {toc}
+
+## Action Submittals {toc}
+
+### The Contractor shall submit the items indicated in the datasheet for the Engineer of Record's review before procurement of waterproofing materials.
+- Product data for the membrane, primer, detail tapes and mastics, reinforcing fabric, termination bars, and sealants, identifying each product by its published designation and thickness or application rate
+- Hydrostatic pressure resistance test report for the membrane in accordance with ASTM D5385/D5385M, reporting the head sustained and the duration
+- Performance attribute test reports for wall membranes in accordance with ASTM D7832/D7832M
+- Peel adhesion test report for pre-applied bonded sheet membranes in accordance with ASTM D903, reporting adhesion to concrete cast against the membrane after water immersion
+- Protection course product data, including class in accordance with ASTM D6506/D6506M where an asphalt-based board is proposed, or compressive strength in accordance with ASTM D1621 where a board product is proposed
+- Drainage composite product data, including in-plane flow rate in accordance with ASTM D4716/D4716M at the design normal stress and hydraulic gradient
+- Shop drawings showing the extent of each membrane type, the elevation of the top of waterproofing, transitions between membrane types, and the tie-in to the above-grade water-resistive barrier
+- Detail drawings at inside and outside corners, pipe and conduit penetrations, form-tie and snap-tie locations, construction joints, movement joints, footing-to-wall transitions, and terminations
+- Written confirmation from the membrane manufacturer that the submitted primer, tapes, mastics, sealants, and protection course are compatible with the submitted membrane
+- Installer qualification statement, including the manufacturer approval or license where required by the datasheet
+
+```datasheet
+label: Action Submittals Required
+type: checkbox
+options:
+ - "Product data for membrane, primer, tapes, and accessories"
+ - "Hydrostatic pressure resistance test report"
+ - "Wall membrane performance attribute test reports"
+ - "Peel adhesion test report for pre-applied bonded sheet"
+ - "Protection course product data"
+ - "Drainage composite in-plane flow rate report"
+ - "Shop drawings showing membrane extent and transitions"
+ - "Detail drawings at corners, penetrations, joints, and terminations"
+ - "Written material compatibility confirmation"
+ - "Installer qualification statement"
+default:
+ - "Product data for membrane, primer, tapes, and accessories"
+ - "Hydrostatic pressure resistance test report"
+ - "Shop drawings showing membrane extent and transitions"
+ - "Detail drawings at corners, penetrations, joints, and terminations"
+ - "Written material compatibility confirmation"
+ - "Installer qualification statement"
+```
+
+### No portion of the waterproofing installation shall proceed until the action submittals covering that portion have been reviewed and returned.
+
+### Detail drawings shall be project-specific and shall show the actual substrate conditions, not generic conditions reproduced from published literature.
+
+### A generic detail set cannot be checked against the conditions that produce leakage, because the conditions that produce leakage are the ones the published details do not anticipate. {note}
+
+## Informational Submittals {toc}
+
+### The Contractor shall submit the items indicated in the datasheet during the course of the work.
+- Substrate acceptance report signed by the waterproofing installer, recording the surface profile, moisture verification result, and any defects corrected before membrane application
+- Daily application records for each day on which membrane is applied, recording air and surface temperature, the area covered, the material lot numbers used, and the applied thickness or application rate verified in the field
+- Wet-film and dry-film thickness readings for fluid-applied and hot-applied membranes, recorded on a grid across each day's application area
+- Manufacturer field representative reports for each site visit, recording the observations made and any corrective work directed
+- Field watertightness test reports for each area tested, recording the method, the duration, the observed result, and the location of any leak found
+
+```datasheet
+label: Informational Submittals Required
+type: checkbox
+options:
+ - "Substrate acceptance report signed by the installer"
+ - "Daily application records"
+ - "Wet-film and dry-film thickness readings"
+ - "Manufacturer field representative reports"
+ - "Field watertightness test reports"
+default:
+ - "Substrate acceptance report signed by the installer"
+ - "Daily application records"
+ - "Manufacturer field representative reports"
+ - "Field watertightness test reports"
+```
+
+## Closeout Submittals {toc}
+
+### The Contractor shall submit the items indicated in the datasheet before the waterproofing installation is accepted.
+- Record drawings showing the as-installed extent of each membrane type, the elevation of the top of waterproofing, and the locations of transitions between membrane types
+- Manufacturer's written warranty made out to the Owner, in the form and for the period indicated in the datasheet
+- Installer's written workmanship warranty made out to the Owner, for the period indicated in the datasheet
+- Repair procedure covering the installed membrane, identifying the materials and the sequence for repairing a defect discovered after backfill
+- Photographic record of the completed membrane at penetrations, joints, corners, and terminations, indexed to the record drawings and taken before the protection course was installed
+
+```datasheet
+label: Closeout Submittals Required
+type: checkbox
+options:
+ - "Record drawings of as-installed membrane extent"
+ - "Manufacturer's written warranty made out to the Owner"
+ - "Installer's written workmanship warranty made out to the Owner"
+ - "Membrane repair procedure"
+ - "Indexed photographic record of detail locations"
+default:
+ - "Record drawings of as-installed membrane extent"
+ - "Manufacturer's written warranty made out to the Owner"
+ - "Installer's written workmanship warranty made out to the Owner"
+ - "Indexed photographic record of detail locations"
+```
+
+### The photographic record is the only means by which a detail can be examined after backfill, and it is the record that determines whether a later leak is investigated as a workmanship defect or as a design condition. {note}
+
+# Quality Assurance {toc}
+
+## Installer Qualifications {toc}
+
+### The waterproofing installer's manufacturer approval shall be as indicated in the datasheet.
+
+```datasheet
+label: Installer Manufacturer Approval
+type: radio
+options:
+ - "Required"
+ - "Not required"
+default: "Required"
+```
+
+### The waterproofing installer shall have completed below-grade waterproofing work of comparable membrane type and comparable groundwater condition for not less than the period indicated in the datasheet.
+
+```datasheet
+label: Minimum Installer Experience
+type: range
+unit: 'years'
+min: 0
+max: 20
+setpoints: [0, 2, 3, 5, 10, 20]
+default: 5
+```
+
+### A single supervisor employed by the waterproofing installer shall be present on site whenever membrane, primer, or detail materials are being applied.
+
+### Where the installer's manufacturer approval lapses or is withdrawn during the course of the work, the Contractor shall notify the Engineer of Record in writing within 5 business days and shall suspend membrane application until a replacement installer is accepted.
+
+## Pre-Installation Conference {toc}
+
+### The Contractor shall convene a pre-installation conference on site before any substrate preparation for waterproofing begins.
+
+### The pre-installation conference shall be attended by the Contractor, the concrete subcontractor, the waterproofing installer, the earthwork subcontractor, the trades whose work penetrates the waterproofed surfaces, the membrane manufacturer's field representative where required by the datasheet, and the Engineer of Record.
+
+### The conference shall review the substrate acceptance criteria, the sequence of membrane application relative to concrete placement and backfill, the detailing at each penetration and joint condition, the assignment of the tie-in to the above-grade water-resistive barrier, the protection and drainage sequence, and the watertightness test plan.
+
+### The Contractor shall record the conference in a written report distributed to every attendee within 5 business days, and the report shall state each unresolved item and the party responsible for resolving it.
+
+### The pre-installation conference exists because the below-grade membrane is installed by one trade across surfaces built by another and penetrated by several more, and each of those interfaces is a location at which no single trade owns the result. {note}
+
+## Manufacturer Field Representation {toc}
+
+### The membrane manufacturer's field representative shall make not less than the number of site visits indicated in the datasheet.
+
+```datasheet
+label: Manufacturer Field Representative — Minimum Site Visits
+type: range
+unit: 'visits'
+min: 0
+max: 12
+setpoints: [0, 1, 2, 4, 6, 12]
+```
+
+### Where one or more site visits are indicated in the datasheet, one visit shall occur on the first day of membrane application.
+
+### The manufacturer's field representative shall have no authority to waive a requirement of the Contract Documents, and any deviation the representative recommends shall be submitted to the Engineer of Record for written direction before it is executed.
+
+# Design Groundwater Basis {toc}
+
+## The design groundwater condition shall be as indicated in the datasheet and shall be the same condition used for the [[sync/foundation-drainage]] scope.
+
+```datasheet
+label: Design Groundwater Condition
+type: radio
+options:
+ - "Non-hydrostatic"
+ - "Intermittently hydrostatic"
+ - "Continuously hydrostatic"
+drawing_ref: "geotechnical investigation report"
+default: deferred
+```
+
+## The three design groundwater conditions are distinguished by where the seasonal high water table stands relative to the below-grade assembly. {note}
+- Non-hydrostatic: the seasonal high water table remains below the underside of the lowest slab, and the assembly is exposed to soil moisture, perched water, and infiltration through backfill
+- Intermittently hydrostatic: the seasonal high water table rises into the below-grade assembly for part of the year
+- Continuously hydrostatic: the water table stands at or above the lowest slab elevation for most of the year
+
+## The design hydrostatic head at the lowest waterproofed elevation shall be as indicated in the datasheet.
+
+```datasheet
+label: Design Hydrostatic Head at the Lowest Waterproofed Elevation
+type: range
+unit: 'ft'
+min: 0
+max: 100
+step: 1
+drawing_ref: "geotechnical investigation report"
+default: deferred
+```
+
+## The design groundwater condition selects the class of protection, and the design hydrostatic head sets the magnitude the membrane and its details must resist. A condition can be intermittently hydrostatic at 2 ft of head or at 20 ft, and those two projects do not take the same membrane, the same lap, or the same detail at a penetration. {note}
+
+## Where the design groundwater condition is non-hydrostatic, the code trigger for waterproofing is not met and the assembly is dampproofed instead; the datasheet records that outcome by indicating the waterproofing material type as not required. {note}
+
+## Owners on some projects require waterproofing where the code requires only dampproofing, and that is a program decision rather than a code determination. Where the below-grade space holds contents whose damage cost exceeds the cost of the assembly, the waterproofing decision follows from the consequence of a leak rather than from the water table elevation. {note}
+
+# Waterproofing System Selection {toc}
+
+## The application method for below-grade wall waterproofing shall be as indicated in the datasheet.
+
+```datasheet
+label: Wall Waterproofing Application Method
+type: radio
+options:
+ - "Positive-side, applied to the outboard face after concrete placement"
+ - "Negative-side, applied to the inboard face after concrete placement"
+ - "Pre-applied blindside, applied before concrete placement"
+drawing_ref: "foundation plan and excavation support drawings"
+default: deferred
+```
+
+## The application method follows from how the wall is built rather than from a preference among membranes. A wall built inside an open excavation presents its outboard face for positive-side work; a wall cast against a soldier pile and lagging wall, a slurry wall, or a shotcrete face has no accessible outboard face and takes a pre-applied membrane installed against the support of excavation before the reinforcing and concrete go in; a wall already built and backfilled presents only its inboard face. {note}
+
+## Negative-side waterproofing leaves the structural concrete saturated because the water is stopped at the interior face rather than at the exterior face. Where the concrete contains embedded metal, is subject to freeze-thaw cycling, or carries a finish sensitive to alkalinity, that saturation is a condition the design must account for. {note}
+
+## The waterproofing material type for below-grade walls shall be as indicated in the datasheet.
+
+```datasheet
+label: Wall Waterproofing Material Type
+type: select
+options:
+ - "Self-adhering modified bituminous sheet"
+ - "Cold fluid-applied elastomeric membrane"
+ - "Hot-applied rubberized asphalt"
+ - "Sodium bentonite geotextile composite"
+ - "Pre-applied bonded sheet membrane"
+ - "Surface-applied cementitious crystalline coating"
+ - "Not required"
+```
+
+## The waterproofing material type beneath slabs shall be as indicated in the datasheet.
+
+```datasheet
+label: Slab Waterproofing Material Type
+type: select
+options:
+ - "Self-adhering modified bituminous sheet"
+ - "Cold fluid-applied elastomeric membrane"
+ - "Hot-applied rubberized asphalt"
+ - "Sodium bentonite geotextile composite"
+ - "Pre-applied bonded sheet membrane"
+ - "Surface-applied cementitious crystalline coating"
+ - "Not required"
+```
+
+## The wall material and the slab material are separate selections because they are applied under different conditions. The slab membrane is placed on a mud slab or prepared subgrade and is loaded in compression by the slab cast on it; the wall membrane is applied to a vertical face and is loaded by backfill and by the drainage layer bearing against it. {note}
+
+## Where the wall waterproofing material type is indicated as not required, below-grade walls shall be dampproofed in accordance with [[sync/dampproofing]].
+
+## Where the slab waterproofing material type is indicated as not required, an under-slab vapor retarder shall be provided in accordance with [[sync/vapor-barriers-under-slab]] where required by the design.
+
+## Where the wall application method is pre-applied blindside, the wall waterproofing material shall be a type formulated for pre-application that develops a bond to the concrete cast against it or that seals against the concrete by swelling.
+
+## A pre-applied membrane that is not bonded to the concrete leaves an annular space between the membrane and the wall. Water entering that space at a single defect migrates laterally along the wall and appears at the interior at a location unrelated to the defect, which is why the defect cannot be located from the interior symptom. {note}
+
+## Where the wall application method is negative-side, the wall waterproofing material shall be a type that resists the applied head from the side opposite the water.
+
+## Where a single below-grade enclosure uses more than one waterproofing material type, the transition between the two shall be shown on the shop drawings and detailed with a material the manufacturers of both membranes have confirmed in writing to be compatible with their products.
+
+## The membrane shall be documented, by test in accordance with ASTM D5385/D5385M, to resist a hydrostatic head not less than the design hydrostatic head indicated in the datasheet.
+
+## ASTM D5385/D5385M states that no correlation has been established between performance in the laboratory test and performance in the field. A published head rating establishes the resistance of the membrane sheet under controlled laboratory conditions; it is not a prediction of the watertightness of the installed assembly, which is governed by the details and the substrate. {note}
+
+# Self-Adhering Modified Bituminous Sheet Membrane {toc}
+
+## Requirements in this article apply where the wall or slab waterproofing material type indicated in the datasheet is self-adhering modified bituminous sheet.
+
+## Self-adhering modified bituminous sheet is a factory-laminated roll product consisting of a rubberized asphalt adhesive compound bonded to a carrier film, supplied with a release liner and applied cold. Its thickness is controlled in the factory, so the field variable is adhesion rather than applied thickness. {note}
+
+## The minimum thickness of self-adhering sheet membrane on walls shall be as indicated in the datasheet.
+
+```datasheet
+label: Self-Adhering Sheet Membrane — Minimum Thickness on Walls
+type: range
+unit: 'mil'
+min: 40
+max: 100
+setpoints: [40, 50, 60, 80, 100]
+```
+
+## The minimum thickness of self-adhering sheet membrane beneath slabs shall be as indicated in the datasheet.
+
+```datasheet
+label: Self-Adhering Sheet Membrane — Minimum Thickness Beneath Slabs
+type: range
+unit: 'mil'
+min: 40
+max: 120
+setpoints: [40, 60, 80, 100, 120]
+```
+
+## The membrane thickness selected shall not be less than the thickness for which the manufacturer publishes compliance with the design hydrostatic head indicated in the datasheet.
+
+## Membrane beneath a slab carries the construction traffic, the reinforcing placement, and the concrete placement operation before it is ever loaded by water, and the damage it takes is concentrated in that window rather than in service. Thickness on a slab is therefore a puncture and abuse decision as much as a hydrostatic one. {note}
+
+## The membrane shall be rolled with a weighted roller over the full sheet area, including laps, immediately after the release liner is removed and the sheet is positioned.
+
+## Self-adhering sheet develops its bond under pressure, not under contact. A sheet placed by hand and not rolled is in contact with the substrate and is not adhered to it, and the difference is not visible on the finished surface. {note}
+
+## Sheets shall be applied to vertical surfaces in lengths that can be positioned and rolled without the sheet folding back on itself.
+
+## Fishmouths, wrinkles, and blisters shall be slit, pressed flat, and covered with a patch of the same membrane extending not less than 6 in. beyond the slit in every direction.
+
+# Cold Fluid-Applied Elastomeric Membrane {toc}
+
+## Requirements in this article apply where the wall or slab waterproofing material type indicated in the datasheet is a cold fluid-applied elastomeric membrane.
+
+## Cold fluid-applied membrane is applied as a liquid and cures in place to a seamless film. It conforms to irregular substrates and complex penetrations without seams, and its thickness is established in the field by the applicator rather than in the factory. {note}
+
+## The membrane shall comply with ASTM C836/C836M and shall be applied in accordance with ASTM C898/C898M.
+
+## The minimum dry-film thickness of the cold fluid-applied membrane shall be as indicated in the datasheet.
+
+```datasheet
+label: Cold Fluid-Applied Membrane — Minimum Dry-Film Thickness
+type: range
+unit: 'mil'
+min: 40
+max: 125
+setpoints: [40, 60, 80, 100, 125]
+default: 60
+```
+
+## The number of coats in which the cold fluid-applied membrane is applied shall be as indicated in the datasheet.
+
+```datasheet
+label: Cold Fluid-Applied Membrane — Number of Coats
+type: range
+unit: 'coats'
+min: 1
+max: 3
+setpoints: [1, 2, 3]
+default: 2
+```
+
+## The extent of reinforcing fabric in the cold fluid-applied membrane shall be as indicated in the datasheet.
+
+```datasheet
+label: Cold Fluid-Applied Membrane — Reinforcing Fabric Extent
+type: radio
+options:
+ - "Full-field reinforcement"
+ - "Reinforcement at detail locations"
+ - "No reinforcement"
+```
+
+## Reinforcing fabric holds the wet film at its intended thickness on a vertical surface and bridges movement at a crack or joint beneath the membrane. A field without reinforcement thins at the top of each vertical run as the wet material sags, and the thinnest point is the point at which the film is tested by head. {note}
+
+## Where more than one coat is indicated, each coat shall be applied in a direction perpendicular to the coat beneath it, and each coat shall be applied within the recoat window published by the manufacturer for the substrate temperature at the time of application.
+
+## Wet-film thickness shall be verified with a wet-film gauge at intervals not exceeding 100 ft² during application of each coat, and dry-film thickness shall be verified after cure at intervals not exceeding 500 ft².
+
+## Fluid-applied thickness is verified during application because it cannot be corrected afterward without recoating the area, and a fluid-applied membrane that cures thin looks identical to one that cures at the specified thickness. {note}
+
+# Hot-Applied Rubberized Asphalt Membrane {toc}
+
+## Requirements in this article apply where the wall or slab waterproofing material type indicated in the datasheet is hot-applied rubberized asphalt.
+
+## Hot-applied rubberized asphalt is heated to a pourable consistency, applied in a monolithic layer with an embedded reinforcing sheet, and cools to a self-healing membrane of substantial thickness. Its thickness and its ability to reseal around a small puncture are what distinguish it from the cold-applied families. {note}
+
+## The minimum total applied thickness of hot-applied rubberized asphalt shall be as indicated in the datasheet.
+
+```datasheet
+label: Hot-Applied Rubberized Asphalt — Minimum Total Applied Thickness
+type: range
+unit: 'mil'
+min: 90
+max: 250
+setpoints: [90, 125, 180, 215, 250]
+default: 215
+```
+
+## The membrane shall be applied in two coats with a reinforcing sheet fully embedded between them.
+
+## The melter shall be equipped with a working thermometer indicating the temperature of the material and with a mechanical agitator that operates continuously while the material is heated.
+
+## Material heated above the manufacturer's published maximum safe heating temperature, or held at application temperature longer than the manufacturer's published maximum holding time, shall be removed from the melter and discarded at the Contractor's cost.
+
+## Rubberized asphalt degrades by prolonged heating rather than by a single overheating event, and the degradation is not apparent in the applied material. The melter thermometer and the holding-time limit exist because the failure is a materials failure that cannot be found by inspecting the finished membrane. {note}
+
+## Applied thickness shall be verified with a depth gauge at intervals not exceeding 100 ft² while the material is still workable.
+
+# Sodium Bentonite Geotextile Composite Membrane {toc}
+
+## Requirements in this article apply where the wall or slab waterproofing material type indicated in the datasheet is a sodium bentonite geotextile composite.
+
+## Sodium bentonite geotextile composite is a panel of granular sodium bentonite contained between two needle-punched geotextiles. It waterproofs by hydrating on contact with water and swelling against the confinement of the surrounding construction, so it seals rather than sheds, and it can reseal around a puncture that stays confined. {note}
+
+## The system shall be used in accordance with ASTM D8425.
+
+## The minimum bentonite mass per unit area of the composite shall be as indicated in the datasheet.
+
+```datasheet
+label: Sodium Bentonite Composite — Minimum Bentonite Mass per Unit Area
+type: range
+unit: 'lb/ft²'
+min: 0.75
+max: 1.5
+setpoints: [0.75, 1.0, 1.25, 1.5]
+default: 1.0
+```
+
+## Bentonite composite panels shall be confined on all sides by the surrounding construction, by the concrete cast against them, or by mechanically restrained backfill before the bentonite is allowed to hydrate.
+
+## Bentonite that hydrates without confinement expands, loses density, and does not recover that density when it dries. An unconfined panel that takes rain in the excavation before the wall is cast is spent before it is loaded. {note}
+
+## Panels shall be protected from precipitation and from standing water in the excavation until they are confined, and panels that have hydrated before confinement shall be removed and replaced at the Contractor's cost.
+
+## ASTM D8425 does not cover bentonite composites installed against masonry, precast concrete, or shotcrete, and it does not cover bentonite bonded to a geomembrane, corrugated-paper-carrier bentonite, or spray-applied bentonite. Where the substrate or the product falls outside that coverage, the design basis for the installation comes from the manufacturer's published data rather than from the ASTM guide. {note}
+
+# Pre-Applied Bonded Sheet Membrane {toc}
+
+## Requirements in this article apply where the wall or slab waterproofing material type indicated in the datasheet is a pre-applied bonded sheet membrane.
+
+## Pre-applied bonded sheet membrane is a thermoplastic carrier sheet coated with an adhesive layer that is activated by the concrete cast against it, forming a bond to the finished structure. Because the bond forms during concrete placement, the membrane is installed with its adhesive face outward against the excavation support and is never accessible again. {note}
+
+## The minimum total thickness of the pre-applied bonded sheet membrane shall be as indicated in the datasheet.
+
+```datasheet
+label: Pre-Applied Bonded Sheet Membrane — Minimum Total Thickness
+type: range
+unit: 'mil'
+min: 30
+max: 100
+setpoints: [30, 40, 50, 60, 80, 100]
+```
+
+## The minimum peel adhesion of the pre-applied bonded sheet membrane to concrete cast against it shall be as indicated in the datasheet, tested in accordance with ASTM D903 after water immersion.
+
+```datasheet
+label: Pre-Applied Bonded Sheet Membrane — Minimum Peel Adhesion to Cast Concrete
+type: range
+unit: 'lbf/in'
+min: 2
+max: 15
+step: 1
+```
+
+## Peel adhesion after immersion is the property that distinguishes a pre-applied bonded membrane from a loose-laid sheet. A bond that survives dry testing but releases after immersion produces an unbonded membrane in service, which is the condition under which a single defect drains the whole wall. {note}
+
+## The membrane shall be installed with the adhesive face oriented toward the concrete to be cast and shall be secured to the excavation support so that it cannot displace during reinforcing placement or concrete placement.
+
+## Reinforcing steel, form ties, chairs, and embedded items shall not penetrate the pre-applied membrane.
+
+## Where a penetration of the pre-applied membrane cannot be avoided, it shall be sealed with the manufacturer's detail materials before concrete is placed, and the location shall be recorded on the record drawings.
+
+## Concrete shall not be placed against the pre-applied membrane until the Contractor has inspected the full membrane area for punctures, unsealed laps, and displacement, and has recorded that inspection.
+
+## The inspection before concrete placement is the last opportunity to see this membrane. After the pour there is no side from which a defect can be found, no side from which it can be repaired, and no relationship between where water appears inside and where it entered. {note}
+
+# Surface-Applied Cementitious Crystalline Coating {toc}
+
+## Requirements in this article apply where the wall or slab waterproofing material type indicated in the datasheet is a surface-applied cementitious crystalline coating.
+
+## Surface-applied cementitious crystalline coating is a cement-based slurry containing reactive chemicals that migrate into the concrete pore structure and form insoluble crystals in the presence of water, reducing the permeability of the concrete itself rather than forming a separate film over it. Because the treatment becomes part of the concrete, it can be applied to the face opposite the water. {note}
+
+## The number of coats of cementitious crystalline coating shall be as indicated in the datasheet.
+
+```datasheet
+label: Cementitious Crystalline Coating — Number of Coats
+type: range
+unit: 'coats'
+min: 1
+max: 3
+setpoints: [1, 2, 3]
+default: 2
+```
+
+## The concrete substrate shall be saturated surface-dry at the time the coating is applied, and the coating shall be wet-cured for the period published by the manufacturer.
+
+## A crystalline coating reacts with water in the concrete. Applied to a dry substrate or left to dry before it has reacted, the material remains a surface film with no crystal growth in the pore structure, which is the mechanism the treatment is selected for. {note}
+
+## Cracks, honeycomb, cold joints, tie holes, and any other discontinuity in the concrete shall be routed and repaired before the coating is applied.
+
+## A crystalline treatment reduces the permeability of sound concrete and does not span a discontinuity. Where a crack is wider than the crystal growth can bridge, the treatment leaves the crack as the path it was. {note}
+
+# Concrete Substrate Preparation {toc}
+
+## Concrete surfaces receiving an adhered membrane shall be prepared in accordance with ASTM D5295/D5295M.
+
+## The minimum age of the concrete substrate before membrane application shall be as indicated in the datasheet.
+
+```datasheet
+label: Concrete Substrate — Minimum Age Before Membrane Application
+type: range
+unit: 'days'
+min: 0
+max: 28
+setpoints: [0, 3, 7, 14, 21, 28]
+default: 7
+```
+
+## Where the membrane manufacturer publishes a minimum substrate age for the specific product that differs from the datasheet value, the longer period shall govern.
+
+## Products formulated for application to green concrete carry a published minimum age shorter than the value most projects specify, and the datasheet minimum can be set to zero where such a product is selected and the schedule requires it. {note}
+
+## The method of verifying concrete surface moisture before membrane application shall be as indicated in the datasheet.
+
+```datasheet
+label: Concrete Surface Moisture Verification Method
+type: radio
+options:
+ - "Plastic sheet method"
+ - "Anhydrous calcium chloride method"
+ - "In-situ relative humidity probe"
+ - "Not required"
+default: "Plastic sheet method"
+```
+
+## Where the plastic sheet method is indicated, the test shall be performed in accordance with ASTM D4263, the sheet shall remain in place not less than 16 h, and membrane shall not be applied where condensation is present on the underside of the sheet or where the concrete beneath it has darkened.
+
+## Where the anhydrous calcium chloride method is indicated, the test shall be performed in accordance with ASTM F1869; where the in-situ relative humidity probe method is indicated, the test shall be performed in accordance with ASTM F2170.
+
+## The moisture limit for each of these methods shall be the limit published by the membrane manufacturer for the product being applied.
+
+## The minimum concrete surface profile shall be as indicated in the datasheet, evaluated against the ICRI 310.2R replica profiles.
+
+```datasheet
+label: Minimum Concrete Surface Profile
+type: select
+options:
+ - "ICRI CSP 1"
+ - "ICRI CSP 2"
+ - "ICRI CSP 3"
+ - "ICRI CSP 4"
+ - "ICRI CSP 5"
+ - "ICRI CSP 6"
+```
+
+## An adhered sheet membrane and a fluid-applied membrane do not want the same profile. A sheet needs a surface smooth enough to make continuous contact under roller pressure; a fluid-applied coating needs enough texture to key into. Specifying one profile for both leaves one of them poorly bonded. {note}
+
+## The maximum substrate surface irregularity measured under a 10 ft straightedge shall be as indicated in the datasheet.
+
+```datasheet
+label: Maximum Substrate Surface Irregularity Under a 10 ft Straightedge
+type: range
+unit: 'in'
+min: 0.125
+max: 0.5
+setpoints: [0.125, 0.25, 0.375, 0.5]
+default: 0.25
+```
+
+## Form-tie holes, honeycomb, voids, spalls, and cracks wider than 1/16 in. shall be filled flush with a cementitious repair material compatible with the membrane before the membrane is applied.
+
+## Fins, form offsets, and mortar droppings shall be removed and the surface ground flush.
+
+## Curing compounds, form release agents, laitance, dust, oil, and any other bond-breaking contaminant shall be removed from surfaces receiving an adhered membrane.
+
+## A curing compound is applied by one trade to protect the concrete and removed by another trade to allow the membrane to bond, and the removal is the step that is skipped when the two trades do not meet. This is a standing item for the pre-installation conference. {note}
+
+## The waterproofing installer shall inspect and accept the prepared substrate in writing before membrane application begins, and shall not apply membrane over a substrate the installer has not accepted.
+
+## Where the waterproofing installer and the Contractor disagree whether a prepared substrate is acceptable, the Engineer of Record shall make the initial determination.
+
+## Primer application shall be as indicated in the datasheet.
+
+```datasheet
+label: Primer Application
+type: radio
+options:
+ - "Required on all substrates receiving membrane"
+ - "Not required"
+default: manufacturer
+```
+
+## Where the datasheet leaves primer application to the manufacturer's standard practice, the membrane manufacturer's published substrate and primer schedule for the products supplied shall govern, and the Contractor shall submit that schedule with the product data.
+
+## Primer shall be applied only to the area that can be covered with membrane within the primer's published open time, and primed area that is not covered within that time shall be re-primed.
+
+# Application Temperature and Weather Limits {toc}
+
+## The minimum air and surface temperature during membrane application shall be as indicated in the datasheet.
+
+```datasheet
+label: Minimum Air and Surface Temperature During Application
+type: range
+unit: '°F'
+min: 0
+max: 60
+setpoints: [0, 20, 25, 32, 40, 50, 60]
+```
+
+## Membrane shall not be applied when the air or surface temperature is below the datasheet value or below the membrane manufacturer's published minimum application temperature, whichever is higher.
+
+## Cold-weather formulations of self-adhering sheet and fluid-applied membranes carry published minimum application temperatures below those of the standard formulations, so the datasheet minimum can be set below freezing where such a product is selected. {note}
+
+## Membrane shall not be applied to a substrate carrying frost, ice, standing water, or visible surface moisture.
+
+## Membrane shall not be applied during precipitation, and any membrane, primer, or detail material exposed to precipitation before it has set shall be removed and replaced at the Contractor's cost.
+
+## The maximum period the applied membrane may remain exposed before it is covered by the protection course shall be as indicated in the datasheet.
+
+```datasheet
+label: Maximum Membrane Exposure Before Cover
+type: range
+unit: 'days'
+min: 1
+max: 180
+setpoints: [1, 7, 14, 30, 60, 90, 180]
+```
+
+## Where the membrane manufacturer publishes a maximum exposure period for the product shorter than the datasheet value, the shorter period shall govern.
+
+## The exposure limit exists because ultraviolet radiation and thermal cycling degrade most below-grade membranes, which are formulated for a buried service life rather than an exposed one. On a schedule where the excavation stays open through a season, this limit is the one that gets exceeded. {note}
+
+# Membrane Continuity, Laps, and Terminations {toc}
+
+## The minimum side and end lap for sheet membranes shall be as indicated in the datasheet.
+
+```datasheet
+label: Sheet Membrane Minimum Side and End Lap
+type: range
+unit: 'in'
+min: 2
+max: 12
+setpoints: [2, 2.5, 3, 4, 6, 12]
+```
+
+## Where the membrane manufacturer publishes a minimum lap greater than the datasheet value, the greater lap shall govern.
+
+## Laps on vertical surfaces shall be shingled so that the upper sheet laps over the lower sheet.
+
+## End laps in adjacent courses shall be staggered by not less than 12 in.
+
+## Every lap edge shall be rolled and, where the manufacturer's system includes an edge treatment, sealed with the manufacturer's mastic or tape.
+
+## The membrane shall be continuous across the footing-to-wall transition, and the wall membrane shall lap onto the membrane or the prepared footing surface so that water arriving at the base of the wall cannot enter behind it.
+
+## The membrane termination method at grade shall be as indicated in the datasheet.
+
+```datasheet
+label: Membrane Termination Method at Grade
+type: radio
+options:
+ - "Reglet cut into the substrate with sealant"
+ - "Surface-mounted termination bar with sealant"
+ - "Lapped beneath the water-resistive barrier of the wall above"
+```
+
+## The membrane termination height above finished grade shall be as indicated in the datasheet.
+
+```datasheet
+label: Membrane Termination Height Above Finished Grade
+type: range
+unit: 'in'
+min: 0
+max: 24
+step: 1
+drawing_ref: "wall sections in the contract documents"
+default: deferred
+```
+
+## A termination is the top edge of the system and the point at which the assembly changes from a buried membrane to an above-grade barrier. Water running down the wall above arrives at that edge, so a termination that is only adhered and not mechanically restrained or lapped under the barrier above is a seam facing upward into the flow. {note}
+
+## Where IBC Section 1805.3 governs, wall waterproofing shall extend from the bottom of the wall to not less than 12 in. above the maximum elevation of the groundwater table, and the remainder of the wall above that elevation shall be dampproofed in accordance with [[sync/dampproofing]].
+
+# Detailing at Penetrations, Corners, and Joints {toc}
+
+## Every inside corner, outside corner, penetration, change of plane, and joint in the substrate shall be detailed with reinforcement before the field membrane is applied.
+
+## Detailing before the field membrane means the detail is complete and inspectable on its own, and the field membrane laps over a finished detail rather than being asked to form one. {note}
+
+## The inside corner treatment beneath the membrane shall be as indicated in the datasheet.
+
+```datasheet
+label: Inside Corner Treatment
+type: radio
+options:
+ - "Cementitious cant fillet"
+ - "Membrane reinforcing strip centered on the corner"
+ - "Liquid-applied detail bead with reinforcing fabric"
+default: manufacturer
+```
+
+## Where the datasheet leaves the inside corner treatment to the manufacturer's standard practice, the membrane manufacturer's published corner detail for the product supplied shall govern, and the Contractor shall submit that detail with the shop drawings.
+
+## An inside corner asks a sheet membrane to make a 90° bend and stay in contact at the vertex. Without a fillet or a reinforcing strip the sheet bridges the corner, and the void behind it is unsupported membrane directly at the location where the substrate is most likely to crack. {note}
+
+## Outside corners shall be reinforced with a strip of membrane or reinforcing fabric extending not less than 6 in. onto each face before the field membrane is applied.
+
+## The seal at pipe and conduit penetrations shall be as indicated in the datasheet.
+
+```datasheet
+label: Pipe and Conduit Penetration Seal
+type: radio
+options:
+ - "Cast-in sleeve with a mechanical link seal"
+ - "Cast-in puddle flange with the membrane lapped onto the flange"
+ - "Membrane collar with a stainless steel draw band and sealant"
+ - "Hydrophilic waterstop gasket at the annulus"
+```
+
+## Penetrations shall be grouped and located so that the clear distance between adjacent penetrations, and between a penetration and a corner or joint, is not less than the distance required to install the selected detail on all sides.
+
+## A penetration detail that cannot be installed all the way around is not installed. Penetration spacing is set during coordination, before the sleeves are cast, and it is the cheapest point at which this problem is solvable. {note}
+
+## Penetrations shall be cast into the concrete rather than core drilled through waterproofed construction.
+
+## Where a penetration through waterproofed construction must be core drilled after the membrane is in place, the Contractor shall submit the proposed detail for the Engineer of Record's review before drilling, and the membrane shall be reinstated in accordance with the reviewed detail.
+
+## The treatment of construction joints beneath the membrane shall be as indicated in the datasheet.
+
+```datasheet
+label: Construction Joint Treatment Beneath the Membrane
+type: radio
+options:
+ - "Hydrophilic strip waterstop"
+ - "Injection hose system"
+ - "Centerbulb waterstop cast into the joint"
+ - "Crystalline slurry applied over the joint"
+ - "No supplemental joint treatment"
+```
+
+## Waterstops cast into concrete joints shall comply with [[sync/concrete-joints-and-waterstops]], and the joint treatment indicated in the datasheet shall be coordinated with the waterstop type specified there.
+
+## The membrane shall be reinforced over every construction joint and every crack in the substrate wider than 1/16 in. with a strip centered on the joint, extending not less than 6 in. on each side.
+
+## Movement joints shall be detailed with a membrane loop, bellows, or preformed joint cover sized for the design movement, and the detail shall be shown on the shop drawings and reviewed before installation.
+
+## A movement joint detailed as a reinforced crack fails on the first cycle, because the reinforcement is there to restrain movement and the joint exists to accommodate it. The two details are not interchangeable. {note}
+
+## Form ties and snap ties shall be broken back, patched flush with a cementitious repair material, and the patch shall be cured before the membrane is applied over it.
+
+# Protection Course {toc}
+
+## A protection course shall be installed over the completed membrane on all waterproofed surfaces before backfill is placed or before a slab is cast, except where the datasheet indicates a drainage composite serving as the protection course.
+
+## The protection course type shall be as indicated in the datasheet.
+
+```datasheet
+label: Protection Course Type
+type: select
+options:
+ - "Asphalt-based protection board"
+ - "Extruded polystyrene insulation board"
+ - "Expanded polystyrene board"
+ - "Semi-rigid polymeric protection sheet"
+ - "Prefabricated drainage composite serving as the protection course"
+ - "Cementitious protection layer"
+```
+
+## The minimum protection course thickness shall be as indicated in the datasheet.
+
+```datasheet
+label: Protection Course — Minimum Thickness
+type: range
+unit: 'in'
+min: 0.125
+max: 2
+setpoints: [0.125, 0.25, 0.375, 0.5, 1, 1.5, 2]
+```
+
+## Where an asphalt-based protection board is indicated, it shall comply with ASTM D6506/D6506M and the class shall be identified in the product data submittal.
+
+## Where a board product other than an asphalt-based protection board is indicated, its compressive strength shall be reported in accordance with ASTM D1621 in the product data submittal.
+
+## The protection course exists to take the backfill and the compaction equipment so that the membrane does not. The load case it is sized for is placement of angular backfill against a vertical membrane, which is a point-loading condition and not a uniform one. {note}
+
+## The protection course shall be installed with butted joints, shall be held in place by adhesive, by the drainage layer, or by the backfill placed against it, and shall not be fastened through the membrane.
+
+## The protection course shall extend over the full membrane area, including the area within 12 in. of terminations and around penetrations.
+
+## Membrane at terminations and around penetrations is the membrane most exposed to backfill impact and the least reachable for repair, and it is the area from which protection is most often omitted because the board has to be cut to fit. {note}
+
+# Wall Drainage Layer {toc}
+
+## The wall drainage layer type shall be as indicated in the datasheet.
+
+```datasheet
+label: Wall Drainage Layer Type
+type: radio
+options:
+ - "Prefabricated drainage composite over the membrane"
+ - "Free-draining granular backfill against the protection course"
+ - "Rigid drainage insulation board"
+ - "No dedicated wall drainage layer"
+```
+
+## The wall drainage layer shall satisfy the drainage requirements of [[sync/foundation-drainage]] for the design groundwater condition indicated in the datasheet.
+
+## The minimum in-plane flow rate of a prefabricated drainage composite shall be as indicated in the datasheet, tested in accordance with ASTM D4716/D4716M at the design normal stress and hydraulic gradient.
+
+```datasheet
+label: Wall Drainage Composite — Minimum In-Plane Flow Rate
+type: range
+unit: 'gal/min per ft of width'
+min: 1
+max: 40
+step: 1
+```
+
+## In-plane flow rate is reported at a stated normal stress and hydraulic gradient, and it falls as the normal stress rises. A value measured at a low stress does not describe the composite at the bottom of a deep wall, which is where the flow it must carry is greatest. {note}
+
+## The drainage layer shall be carried continuously from the top of the drainage extent shown on the drawings to the perimeter drain, and its bottom edge shall discharge into the drainage aggregate surrounding the perimeter drain.
+
+## A drainage layer that stops above the perimeter drain delivers water to the soil at that elevation rather than to the drain, which loads the wall at the elevation where the head is highest. {note}
+
+## The filter fabric face of a prefabricated drainage composite shall be installed facing the soil, and the fabric shall be lapped not less than 4 in. at panel joints and shall be kept free of soil during installation.
+
+## The drainage composite shall not be installed as a substitute for the protection course unless the datasheet indicates a drainage composite serving as the protection course.
+
+# Field Testing for Watertightness {toc}
+
+## The methods used to verify the watertightness of the installed membrane shall be as indicated in the datasheet.
+
+```datasheet
+label: Field Watertightness Verification Methods
+type: checkbox
+options:
+ - "Flood test of horizontal waterproofing"
+ - "Low-voltage electronic leak detection"
+ - "High-voltage spark electronic leak detection"
+ - "Visual inspection of the completed membrane before cover"
+ - "Adhesion pull testing of the applied membrane"
+default:
+ - "Flood test of horizontal waterproofing"
+ - "Visual inspection of the completed membrane before cover"
+```
+
+## Testing shall be performed after the membrane and all detailing in the area under test are complete and before the protection course, drainage layer, or any overburden is installed.
+
+## A test performed after cover reports that water reached the interior; it does not report where the membrane was breached. Every method below locates the defect only while the membrane is still exposed. {note}
+
+## Flood testing shall be performed in accordance with ASTM D5957.
+
+## The flood test duration shall be as indicated in the datasheet.
+
+```datasheet
+label: Flood Test — Minimum Duration
+type: range
+unit: 'h'
+min: 8
+max: 96
+setpoints: [8, 12, 24, 48, 72, 96]
+default: 24
+```
+
+## The flood test water depth at the high point of the test area shall be as indicated in the datasheet.
+
+```datasheet
+label: Flood Test — Water Depth at the High Point of the Test Area
+type: range
+unit: 'in'
+min: 1
+max: 4
+setpoints: [1, 2, 3, 4]
+default: 2
+```
+
+## ASTM D5957 limits the short-term hydrostatic head to 4 in. of water unless the effect of the increased load on the substrate has been reviewed and approved by a licensed structural engineer. {note}
+
+## Flood testing shall not begin until the membrane materials in the test area have cured, and in no case within 24 h of their installation, or within 48 h where they were installed at an ambient temperature below 60°F.
+
+## The Contractor shall confirm in writing that the structure supporting the test area can carry the weight of the impounded water before the area is flooded, and shall obtain the Engineer of Record's written concurrence before flooding.
+
+## Electronic leak detection shall be performed in accordance with ASTM D7877, and the method used shall match the membrane material and its moisture condition at the time of the survey.
+
+## Electronic leak detection locates a breach by measuring electrical conductance through it, so it requires an electrically insulating membrane over a conductive substrate. Whether the low-voltage or the high-voltage method applies depends on whether the membrane surface is wetted or dry at the time of the survey. {note}
+
+## ASTM D7877 states that electronic leak detection is not intended to replace visual or other methods of inspection and is to be used in conjunction with them. {note}
+
+## The Engineer of Record and the waterproofing installer shall jointly inspect the completed membrane before the protection course is installed, and the inspection shall cover every penetration, corner, joint, transition, and termination in the area.
+
+## Where a test or inspection discloses a defect, the Contractor shall repair the defect in accordance with the reviewed repair procedure and shall repeat the test over the full area originally tested.
+
+## The cost of the repair and the cost of every repeat test following a failed test shall be borne by the Contractor.
+
+## Where the parties disagree whether an observed condition constitutes a defect, the Engineer of Record shall make the initial determination.
+
+# Delivery, Storage, and Handling {toc}
+
+## Materials shall be delivered in the manufacturer's original unopened packaging bearing the product designation, the lot number, and the manufacturer's published storage and shelf-life information.
+
+## Materials shall be stored off the ground, under cover, and within the temperature range published by the manufacturer, and shall not be stored in the excavation.
+
+## Rolls of sheet membrane shall be stored on end on a flat surface and shall not be stacked, laid on their sides, or stored under other materials.
+
+## A roll stored on its side flattens under its own weight, and the resulting distortion does not roll out. It shows up as a sheet that will not lie flat on the wall at exactly the point at which the applicator is trying to keep a lap aligned. {note}
+
+## Material whose published shelf life has expired, and material whose lot number does not appear on the delivered documentation, shall be removed from the site and shall not be incorporated into the work.
+
+## Solvent-based primers and adhesives shall be stored, handled, and disposed of in accordance with the manufacturer's safety data sheets and the requirements of the authority having jurisdiction.
+
+# Backfill Against Waterproofed Surfaces {toc}
+
+## Backfill shall not be placed against a waterproofed wall until the membrane, the protection course, and the drainage layer in that area are complete and have been inspected.
+
+## Backfill shall not be placed against a wall until the wall has attained the strength required to resist the backfill loading, as confirmed in writing by the Engineer of Record.
+
+## The maximum loose lift thickness for backfill placed adjacent to waterproofed surfaces shall be as indicated in the datasheet.
+
+```datasheet
+label: Maximum Backfill Lift Thickness Adjacent to Waterproofed Walls
+type: range
+unit: 'in'
+min: 6
+max: 24
+setpoints: [6, 8, 12, 18, 24]
+```
+
+## The minimum standoff distance within which compaction shall be performed by hand-operated equipment rather than by ride-on or towed equipment shall be as indicated in the datasheet.
+
+```datasheet
+label: Minimum Standoff Distance for Ride-On Compaction Equipment
+type: range
+unit: 'ft'
+min: 0
+max: 20
+setpoints: [0, 3, 5, 10, 20]
+```
+
+## The standoff exists because ride-on compaction equipment transmits a surcharge into the wall and drives angular backfill into the protection course. The wall is designed for the at-rest soil pressure, not for the transient load a vibratory roller applies at the top of a lift. {note}
+
+## Backfill placed against waterproofed surfaces shall be free of debris, frozen material, organic material, and stones larger than the maximum dimension permitted by [[sync/earthwork]] for backfill adjacent to structures.
+
+## Backfill shall be placed in a manner that does not allow material to free-fall against the protection course from a height greater than 5 ft.
+
+## Where the protection course or the drainage layer is displaced or damaged during backfill, the Contractor shall excavate to expose the damage, reinstate the affected materials, and re-inspect the area before backfill resumes, at the Contractor's cost.
+
+# Warranty {toc}
+
+## The form of the manufacturer's warranty shall be as indicated in the datasheet.
+
+```datasheet
+label: Manufacturer Warranty Form
+type: radio
+options:
+ - "Material-only warranty"
+ - "Labor and material warranty"
+ - "No-dollar-limit system warranty"
+```
+
+## The three warranty forms differ in what the Owner recovers, not in how long the membrane lasts. A material-only warranty replaces the failed material; a labor and material warranty adds the cost of installing the replacement; a no-dollar-limit system warranty covers the cost of the repair without a cap tied to the original contract value. None of them cover excavation to reach the membrane unless the warranty says so in its own text. {note}
+
+## The manufacturer's warranty period shall be as indicated in the datasheet, measured from the date of Substantial Completion.
+
+```datasheet
+label: Manufacturer Warranty Period
+type: range
+unit: 'years'
+min: 1
+max: 20
+setpoints: [1, 2, 5, 10, 15, 20]
+default: 5
+```
+
+## The installer's workmanship warranty period shall be as indicated in the datasheet, measured from the date of Substantial Completion.
+
+```datasheet
+label: Installer Workmanship Warranty Period
+type: range
+unit: 'years'
+min: 1
+max: 10
+setpoints: [1, 2, 3, 5, 10]
+default: 2
+```
+
+## The manufacturer's warranty and the installer's warranty shall each be made out to the Owner and shall each be assignable to a subsequent owner of the property once during the warranty period.
+
+## Warranty repairs shall be warranted for a full term equal to the original warranty period measured from the date the repair is accepted, or for the remainder of the original term, whichever ends later.
+
+## The Contractor shall bear the cost of excavating to expose the membrane, of removing and reinstating the protection course and drainage layer, and of restoring paving, landscaping, and site improvements disturbed by a warranty repair, and shall restore each disturbed surface to the condition recorded in the pre-existing-condition survey.
+
+## The Contractor shall record a pre-existing-condition survey of paving, landscaping, and site improvements within the area that would be disturbed by a warranty repair, and shall submit it with the closeout submittals.
+
+## Restoration obligations written as "equal to or better than existing" are unenforceable years later without a record of what existed. The survey is what makes the obligation collectible. {note}
+
+## The Contractor shall bear the cost of repairing damage to interior finishes, stored contents, and building systems caused by water entering through a defect covered by the warranty, up to the limits stated in the Contract Documents.