+---
+title: Architectural Precast Concrete
+category: Structural / Concrete
+toc_depth: 3
+description: >
+ When to use: plant-fabricated, finish-grade precast concrete cladding panels
+ and trim (spandrels, column covers, window surrounds, cornices, reveal panels,
+ medallions, custom profiles) installed as non-loadbearing facade elements on
+ commercial, institutional, healthcare, higher-education, and civic buildings;
+ covers exposed face-mix selection, surface finish treatment, color/texture
+ approval by sample and mockup, cladding connection hardware, erection
+ tolerances, field patching, and PCI Group A1 plant certification.
+ Not intended for: structural/prestressed members — double-tees, hollow-core
+ plank, load-bearing walls, beams, columns (use sync/precast-concrete, the
+ upstream production and structural base reference); site-cast tilt-up (use
+ sync/cast-in-place-concrete); cast stone (use sync/cast-stone); EIFS (use
+ sync/exterior-insulation-and-finish-systems); metal wall panels (use
+ sync/metal-wall-panels); joint sealant product selection (use
+ sync/joint-sealants); shop painting or galvanizing of embeds (use
+ sync/shop-painting-and-galvanizing); precast pipe, culverts, and manholes
+ (governed by their own ASTM product standards).
+---
+
+# Scope {toc}
+
+## This standard covers plant-fabricated, finish-grade architectural precast concrete cladding panels and trim units installed as non-loadbearing facade elements. {note}
+
+## Architectural precast is precast whose primary purpose is appearance: the exposed concrete face is a finished architectural surface, produced under color, texture, and finish controls that structural precast plants are not equipped to deliver. The work includes selection of exposed face-mix ingredients, surface finish treatment, color and texture approval, cladding connection hardware, erection tolerances and joint coordination, field patching and cleaning, and PCI Group A1 plant certification. {note}
+
+## Included unit types are spandrel panels, column covers, cornices and copings, reveal and window-surround panels, medallions, and custom-profile trim. {note}
+
+## Both conventionally reinforced and stainless-reinforced units are covered, in thin-shell-on-backup, solid, and insulated sandwich configurations. {note}
+
+## This standard governs only the non-loadbearing cladding function of these units. {note}
+
+## Where a precast unit simultaneously carries floor or roof gravity load (a loadbearing panel), the structural production, release-strength, and erection-sequence requirements of [[sync/precast-concrete]] also apply and govern the structural function. This standard then governs only the architectural face, finish, and cladding connections of that same unit. {note}
+
+## Relationship to the structural precast standard. {note}
+
+## [[sync/precast-concrete]] already claims architectural cladding within its broad scope, which suits integrated packages where one producer delivers both structure and skin. This standard is the dedicated, finish-first treatment for projects where the cladding is a separate specialty subcontract or where finish quality is the dominant design driver. It treats [[sync/precast-concrete]] as the upstream production and structural base reference and does not restate its mix-production, prestressing, or structural-member provisions. {note}
+
+## The following are excluded and are governed by the standards named. {note}
+- Structural and prestressed members — columns, beams, double-tees, hollow-core plank, load-bearing walls, stair units: [[sync/precast-concrete]].
+- Site-cast tilt-up wall panels lifted into place on site: [[sync/cast-in-place-concrete]] (no SynC standard currently covers tilt-up specifically).
+- Cast stone, a fine-grained precast product simulating cut limestone or masonry, with its own matrix and closer masonry-course tolerances: [[sync/cast-stone]].
+- Exterior insulation and finish systems and stucco cladding: [[sync/exterior-insulation-and-finish-systems]].
+- Metal cladding and metal wall panels: [[sync/metal-wall-panels]].
+- Sealant product selection and installation in panel joints: [[sync/joint-sealants]] (this standard sets joint widths and backup requirements but delegates sealant selection).
+- Post-installed anchors into concrete backup: governed by IBC Chapter 17 special inspection and the anchor manufacturer's ICC-ES evaluation report; referenced but not specified here.
+- Shop painting and galvanizing of embedded steel connection hardware: [[sync/shop-painting-and-galvanizing]].
+- Precast concrete pipe, box culverts, manholes, and underground utility products: governed by their own ASTM product standards.
+
+## Panel type. {note}
+
+## The configuration table below records the unit type so that finish, connection, and tolerance requirements track the geometry. Most commercial and institutional facades are dominated by flat spandrel panels. {note}
+
+```datasheet
+label: Panel Type
+type: select
+options:
+ - Flat spandrel panel
+ - Column cover (3- or 4-sided)
+ - Window surround / reveal panel
+ - Cornice / coping unit
+ - Custom-profile trim (pilaster, medallion, band)
+ - Flat cladding panel (full-story)
+default: Flat spandrel panel
+```
+
+## Structural role. {note}
+
+## The structural role determines whether the structural provisions of [[sync/precast-concrete]] are layered on top of this standard. Non-loadbearing cladding is the default and the only role this standard fully addresses. {note}
+
+```datasheet
+label: Structural Role
+type: radio
+options:
+ - Non-loadbearing (cladding only)
+ - Loadbearing (also carries floor or roof load)
+default: Non-loadbearing (cladding only)
+```
+
+# Referenced Standards {toc}
+
+## Materials, fabrication, 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 |
+|----------|-------|
+| PCI MNL-117-13 | Manual for Quality Control for Plants and Production of Architectural Precast Concrete Products, 4th Edition |
+| PCI MNL-122 | Architectural Precast Concrete (design guide) |
+| PCI MNL-120 | PCI Design Handbook — Precast and Prestressed Concrete, 8th Edition |
+| PCI 135-24 | Specification for Tolerances of Precast Concrete (public-comment draft, 2024) |
+| ACI 318-25 | Building Code Requirements for Structural Concrete and Commentary |
+| ACI 117-10 (R2015) | Specification for Tolerances for Concrete Construction and Materials |
+| ASTM C150/C150M | Portland Cement |
+| ASTM C595/C595M | Blended Hydraulic Cements |
+| ASTM C33/C33M | Concrete Aggregates |
+| ASTM C494/C494M | Chemical Admixtures for Concrete |
+| ASTM C618 | Coal Fly Ash and Raw or Calcined Natural Pozzolan for Use in Concrete |
+| ASTM C1240 | Silica Fume Used in Cementitious Mixtures |
+| ASTM C979/C979M | Pigments for Integrally Colored Concrete |
+| ASTM C39/C39M | Compressive Strength of Cylindrical Concrete Specimens |
+| ASTM A615/A615M | Deformed and Plain Carbon-Steel Bars for Concrete Reinforcement |
+| ASTM A706/A706M | Deformed and Plain Low-Alloy Steel Bars for Concrete Reinforcement |
+| ASTM A276/A276M | Stainless Steel Bars and Shapes |
+| ASTM A666 | Annealed or Cold-Worked Austenitic Stainless Steel Sheet, Strip, Plate, and Flat Bar |
+| ASTM A36/A36M | Carbon Structural Steel |
+| ASTM A123/A123M | Zinc (Hot-Dip Galvanized) Coatings on Iron and Steel Products |
+| ASTM A153/A153M | Zinc Coating (Hot-Dip) on Iron and Steel Hardware |
+| ASTM C920 | Elastomeric Joint Sealants |
+| ASTM C1107/C1107M | Packaged Dry, Hydraulic-Cement Grout (Nonshrink) |
+| AWS D1.1/D1.1M | Structural Welding Code — Steel |
+| IBC Chapter 17 | International Building Code — Special Inspections and Tests |
+| ASCE 7 | Minimum Design Loads and Associated Criteria for Buildings and Other Structures (Chapter 13, nonstructural components) |
+
+# Submittals {toc}
+
+## Action Submittals {toc}
+
+### The Contractor shall submit the following action submittals for review and approval before fabrication begins:
+- Product data for cement, aggregates, pigments, admixtures, reinforcement, connection hardware, bearing pads, and grout.
+- Design mix proportions for each face mix and each backup mix, with the water-cementitious materials ratio stated.
+- Shop drawings showing panel elevations, dimensions, reveal and joint patterns, opening locations, reinforcement, embedded hardware, and connection details.
+- Delegated-design connection calculations sealed by a professional engineer registered in the project jurisdiction.
+- Erection drawings showing panel marks, erection sequence, connection assignments, and field-weld and bolt locations.
+- Finish, color, and texture samples and the schedule of required mockups.
+
+```datasheet
+label: Action Submittals
+type: checkbox
+options:
+ - Product data (materials and hardware)
+ - Face and backup mix designs (w/cm stated)
+ - Fabrication shop drawings
+ - Delegated connection calculations (PE sealed)
+ - Erection drawings
+ - Finish / color / texture samples and mockup schedule
+default:
+ - Product data (materials and hardware)
+ - Face and backup mix designs (w/cm stated)
+ - Fabrication shop drawings
+ - Delegated connection calculations (PE sealed)
+ - Erection drawings
+ - Finish / color / texture samples and mockup schedule
+```
+
+## Informational Submittals {toc}
+
+### The Contractor shall submit the following informational submittals:
+- Current PCI plant certification for the producing plant in the required group.
+- Welder qualification records and welding procedure specifications per AWS D1.1.
+- Concrete test reports (release strength and 28-day compressive strength).
+- Producer's quality-control plan and inspection records.
+- Shipping, storage, and handling protection plan.
+
+```datasheet
+label: Informational Submittals
+type: checkbox
+options:
+ - PCI plant certification
+ - Welder qualifications and WPS
+ - Concrete strength test reports
+ - Producer quality-control plan
+ - Shipping / storage / handling plan
+default:
+ - PCI plant certification
+ - Welder qualifications and WPS
+ - Concrete strength test reports
+ - Producer quality-control plan
+ - Shipping / storage / handling plan
+```
+
+## Closeout Submittals {toc}
+
+### The Contractor shall submit the following closeout submittals before final acceptance:
+- Cleaning and maintenance recommendations for the installed finish.
+- Record erection drawings reflecting as-built panel marks and connections.
+- Special-inspection reports for welding, bolting, and post-installed anchors.
+
+```datasheet
+label: Closeout Submittals
+type: checkbox
+options:
+ - Cleaning and maintenance recommendations
+ - Record erection drawings
+ - Special-inspection reports
+default:
+ - Cleaning and maintenance recommendations
+ - Record erection drawings
+ - Special-inspection reports
+```
+
+# Quality Assurance {toc}
+
+## Why architectural precast carries its own QA regime. {note}
+
+## The finished concrete face is the deliverable. Color uniformity, finish texture, and dimensional precision are achieved through plant disciplines — mockup-controlled finishing, segregated face and backup placement, pigment batching control, and per-panel finish comparison — that a structural precast plant certified only for load-carrying members may not maintain. Specifying architectural cladding under the structural section without invoking PCI MNL-117 and Group A1 certification is a recurring and costly error: structural plants lack the finishing expertise, color controls, and sample-approval workflows that finish-grade work requires. {note}
+
+### The producing plant shall hold current PCI plant certification in the group required below for the duration of fabrication.
+
+### Architectural cladding panels and trim shall be produced under PCI Group A1 (Architectural) certification unless an equivalent program is accepted below.
+
+## Plant certification group. {note}
+
+## Group A1 is the architectural certification and is the default for finish-grade cladding. Group B (structural) is acceptable only for plain, non-color-critical units where the Engineer accepts it in writing. An NPCA certification may be accepted as an alternative where the Engineer determines the producer's architectural controls are equivalent. {note}
+
+```datasheet
+label: Required Plant Certification
+type: radio
+options:
+ - PCI Group A1 (Architectural)
+ - PCI Group B (Structural) — Engineer-accepted
+ - NPCA certification — Engineer-accepted alternative
+default: PCI Group A1 (Architectural)
+```
+
+### Welding of connection hardware shall be performed by welders qualified under AWS D1.1 within the preceding 12 months.
+
+### Field welding, high-strength bolting, and post-installed anchors at panel connections shall be subject to special inspection in accordance with IBC Chapter 17.
+
+## Special inspection is mandatory and is a life-safety requirement, not a discretionary one. {note}
+
+## Connection failures at cladding panels are a falling-hazard risk to occupants and the public. The IBC Chapter 17 special-inspection program shall list welding, high-strength bolting, and post-installed anchors at precast connections; omitting them from the program is a defect that must be corrected before connections are concealed. {note}
+
+## Sample Panels and Mockups {toc}
+
+### The producer shall furnish finish samples and mockups as scheduled below, and no production unit shall be cast for the project until the corresponding finish, color, and texture are accepted in writing.
+
+## Why a full-size mockup is often required. {note}
+
+## A tabletop laboratory sample cannot capture how pigment, aggregate gradation, and finish treatment interact at full scale under natural light. On color-critical facades a 4 ft x 4 ft sample is approved for the finish character, but an 8 ft x 8 ft full-size wall-panel mockup is needed to validate color and texture as the eye will read them on the building. Omitting the full-size mockup on a color-critical facade produces rejected production panels and field RFIs. {note}
+
+### Tabletop finish samples shall be a minimum of 4 ft x 4 ft and shall establish the accepted finish character, aggregate exposure, and texture.
+
+### For color-critical or complex finishes, a full-size wall-panel mockup of at least 8 ft x 8 ft shall be produced and accepted before production casting.
+
+### Where a range of acceptable color is established, the producer shall furnish range panels representing the light, medium, and dark acceptance limits, and production shall fall within that range.
+
+## Mockup scope. {note}
+
+## The required level of mockup is recorded below so that bidders price it correctly. In-place building mockup panels are reserved for the most finish-sensitive projects, where the mockup remains in the completed work. {note}
+
+```datasheet
+label: Mockup Requirement
+type: radio
+options:
+ - Tabletop sample only (4 ft x 4 ft)
+ - Tabletop sample plus full-size wall-panel mockup (8 ft x 8 ft)
+ - In-place building mockup panel (remains in the work)
+default: Tabletop sample plus full-size wall-panel mockup (8 ft x 8 ft)
+```
+
+## Factory Quality Control {toc}
+
+### The producer shall cast and test a minimum of four compressive-strength cylinders per 50 yd³ of face mix and not fewer than four per mix per production day, tested per ASTM C39.
+
+### Each finished unit shall be compared against the accepted mockup at the plant before shipment, and units outside the accepted color and finish range shall be rejected.
+
+# Environmental and Service Conditions {toc}
+
+## Exposure drives material durability selection. {note}
+
+## Exterior cladding is exposed to wind-driven rain, freeze-thaw cycling, ultraviolet light, and — within roughly one mile of saltwater — chloride-laden coastal air. These exposures govern the water-cementitious ratio of the face mix, the corrosion protection of embedded steel, and whether stainless reinforcement is warranted at thin cover. {note}
+
+## Service exposure category. {note}
+
+## The exposure category below selects the durability defaults applied later in this standard. The coastal category triggers stainless embeds and is appropriate for sites within one mile of saltwater. {note}
+
+```datasheet
+label: Service Exposure
+type: select
+options:
+ - Interior / protected
+ - Exterior, non-coastal
+ - Exterior, coastal (within 1 mile of saltwater)
+default: Exterior, non-coastal
+```
+
+### Face mix for exterior exposure shall be proportioned for a maximum water-cementitious materials ratio of 0.40.
+
+```datasheet
+label: Maximum Water-Cementitious Materials Ratio (Face Mix)
+type: range
+min: 0.36
+max: 0.45
+step: 0.01
+default: 0.40
+unit: w/cm
+```
+
+## Seismic and wind demand. {note}
+
+## Cladding panels and their connections are nonstructural components under ASCE 7 Chapter 13. Connection design forces are derived from the Chapter 13 Fp equation, with a component importance factor Ip = 1.0 for typical cladding. Connections shall accommodate the seismic story drift of the supporting structure without transferring in-plane frame load into the panel. {note}
+
+### Cladding panels and connections shall be designed for the wind and seismic forces determined under ASCE 7, including the Chapter 13 nonstructural-component provisions.
+
+### Connections shall accommodate the seismic and thermal movements of the supporting structure without inducing load into the panel face.
+
+### Precast connections shall not rigidly bridge a building expansion or seismic separation joint.
+
+## Why panels must not bridge separation joints. {note}
+
+## A connection that rigidly spans a building expansion or seismic separation joint will be torn in the first significant thermal cycle or seismic event. Separation joints in the cladding shall be located to coincide with the structure's expansion and seismic joints. {note}
+
+# Concrete Materials and Mix {toc}
+
+## Face mix versus backup concrete. {note}
+
+## A thin-shell architectural panel is cast in two concretes placed wet-on-wet: an exposed face mix carrying the cement, aggregate, and pigment that produce the finish, bonded to a grey backup concrete carrying the reinforcement and connection embeds. The face mix is selected for appearance and durability; the backup concrete for strength and economy. On solid panels a single architectural mix is used throughout. {note}
+
+### Portland cement shall conform to ASTM C150/C150M; blended hydraulic cements for backup concrete shall conform to ASTM C595/C595M.
+
+### Face-mix cement color shall match the accepted mockup, using white cement, grey cement, or a blend as required to achieve the accepted color.
+
+### Fine and coarse aggregates shall conform to ASTM C33/C33M as a minimum, and facing aggregates shall meet or exceed those limits.
+
+### Chemical admixtures shall conform to ASTM C494/C494M; integral color pigments shall conform to ASTM C979/C979M; silica fume, where used, shall conform to ASTM C1240.
+
+### Fly ash with dark or variable color shall not be used in exposed face mixes.
+
+## Why fly-ash color matters in the face. {note}
+
+## Variable-color fly ash conforming to ASTM C618 is acceptable structurally but causes uncontrolled batch-to-batch color variation in an exposed face. Specify white-cement face mixes, or confirm a consistent fly-ash color with the producer before approving the face-mix design. {note}
+
+## Face Mix Selection {toc}
+
+## Cement color and aggregate define the field color. {note}
+
+## The base color of the panel is set by the cement (white, grey, or blended), the facing aggregate (local crushed stone, quartz, marble, granite chips, or river gravel), the maximum aggregate size, and any integral pigment. These choices are recorded below and locked against the accepted mockup. {note}
+
+```datasheet
+label: Face-Mix Cement
+type: radio
+options:
+ - White portland cement
+ - Grey portland cement
+ - White/grey blend
+default: Grey portland cement
+```
+
+```datasheet
+label: Facing Aggregate
+type: select
+options:
+ - Local crushed stone
+ - Quartz
+ - Marble chips
+ - Granite chips
+ - River gravel
+default: Local crushed stone
+```
+
+```datasheet
+label: Maximum Facing Aggregate Size
+type: select
+options:
+ - 3/8 in.
+ - 1/2 in.
+ - 3/4 in.
+ - 1 in.
+default: 3/8 in.
+unit: in.
+```
+
+### Integral pigment, where used, shall be iron-oxide pigment conforming to ASTM C979/C979M, dosed by weight of cementitious material.
+
+## Pigment loading. {note}
+
+## Iron-oxide pigment is typically dosed between 3% and 8% by weight of cementitious material; loading above this range yields diminishing color return and raises cost. The accepted mockup, not the dosage number, is the acceptance reference. {note}
+
+```datasheet
+label: Pigment Loading (by weight of cementitious)
+type: range
+min: 0
+max: 10
+step: 1
+default: 0
+unit: "%"
+```
+
+## Compressive Strength {toc}
+
+### Face-mix concrete shall attain a minimum 28-day compressive strength of 5,000 psi.
+
+```datasheet
+label: Face-Mix 28-Day Compressive Strength (min)
+type: range
+min: 5000
+max: 7000
+step: 500
+default: 5000
+unit: psi
+```
+
+### Backup concrete shall attain a minimum 28-day compressive strength of 4,000 psi.
+
+```datasheet
+label: Backup Concrete 28-Day Compressive Strength (min)
+type: range
+min: 4000
+max: 6000
+step: 500
+default: 4000
+unit: psi
+```
+
+### Units shall attain the release strength required for stripping and handling before being removed from the form, as determined by the delegated engineer.
+
+## Release strength. {note}
+
+## Units must reach a handling-safe strength before stripping; a common default is 3,500 psi, but the delegated engineer may require higher where panel geometry or lifting stresses demand it. {note}
+
+```datasheet
+label: Release Strength for Handling (min)
+type: range
+min: 3000
+max: 4500
+step: 250
+default: 3500
+unit: psi
+```
+
+# Reinforcement and Embedded Hardware {toc}
+
+## Reinforcement choice follows cover and exposure. {note}
+
+## Conventional carbon-steel reinforcement is standard, but the minimum cover required to protect it (1.5 in. for exterior carbon steel per ACI 318-25 Table 20.6.1.3) can exceed the thickness available in a thin face wythe. Stainless reinforcement permits a reduced cover of about 0.75 in., which is why thin panels and coastal projects increasingly use Type 316 stainless or fiber-reinforced-polymer bars. {note}
+
+### Deformed carbon-steel bars shall conform to ASTM A615/A615M Grade 60; in Seismic Design Categories D through F, bars shall conform to ASTM A706/A706M where required by ACI 318.
+
+### Stainless reinforcing bars, where specified, shall conform to ASTM A276/A276M, Type 304 or Type 316.
+
+### Carbon-steel reinforcement in exterior exposure shall have a minimum concrete cover of 1.5 in. per ACI 318-25 unless protected by an accepted alternative.
+
+## Reinforcement type. {note}
+
+## The reinforcement system is recorded below so that cover, panel thickness, and corrosion protection are coordinated. Stainless is the durable choice for thin and coastal panels; carbon steel with adequate cover suits typical exterior work. {note}
+
+```datasheet
+label: Reinforcement Type
+type: select
+options:
+ - Carbon steel (ASTM A615 Grade 60)
+ - Carbon steel, epoxy-coated
+ - Carbon steel, hot-dip galvanized
+ - Stainless steel Type 304
+ - Stainless steel Type 316
+default: Carbon steel (ASTM A615 Grade 60)
+```
+
+## Embedded Connection Hardware {toc}
+
+### Embedded plates, angles, and weld-on studs of carbon steel shall conform to ASTM A36/A36M.
+
+### Carbon-steel embeds in exterior service shall be hot-dip galvanized to ASTM A123/A123M, Class C minimum (1.5 oz/ft²); bolts, nuts, and miscellaneous hardware shall be galvanized to ASTM A153/A153M.
+
+### In coastal exposure within one mile of saltwater, embedded connection hardware shall be stainless steel — Type 304 minimum, Type 316 where specified — conforming to ASTM A276/A276M or ASTM A666.
+
+## Why bare or thin-cover embeds fail. {note}
+
+## Uncovered or thin-cover carbon-steel embeds in an exterior panel corrode, and the expanding corrosion product spalls the concrete face — a visible and progressive defect. The default is galvanized A36 for interior or protected locations and stainless for exposed exterior; specifying bare carbon steel at the face is an error. {note}
+
+## Embed corrosion protection. {note}
+
+## The corrosion protection of embedded hardware is recorded below and is driven by the service exposure selected earlier. Shop application of these coatings is governed by [[sync/shop-painting-and-galvanizing]] and [[sync/structural-steel-connections]]. {note}
+
+```datasheet
+label: Embed Corrosion Protection
+type: radio
+options:
+ - Galvanized carbon steel (interior / protected)
+ - Galvanized carbon steel (exterior)
+ - Stainless steel Type 304
+ - Stainless steel Type 316 (coastal)
+default: Galvanized carbon steel (exterior)
+```
+
+### Non-shrink grout at bearing pads and connection pockets shall conform to ASTM C1107/C1107M.
+
+# Panel Construction {toc}
+
+## Panel cross-section. {note}
+
+## The panel cross-section determines weight, thermal performance, and connection design. A thin-shell face on grey backup is the most common cladding section; insulated sandwich panels integrate continuous insulation into the cladding; solid panels are used where thickness is not a concern. {note}
+
+```datasheet
+label: Panel Cross-Section
+type: radio
+options:
+ - Thin-shell face on backup concrete
+ - Solid single-mix panel
+ - Insulated sandwich (face wythe + insulation + backup wythe)
+default: Thin-shell face on backup concrete
+```
+
+### Thin-shell face panels with normal reinforcement shall have a minimum face-wythe thickness of 3-1/2 in. per PCI MNL-117.
+
+## Reduced thickness with stainless reinforcement. {note}
+
+## A 3 in. face wythe is achievable only with stainless reinforcement at reduced cover and only by specific project approval; the standard minimum for normally reinforced thin shells remains 3-1/2 in. {note}
+
+### Insulated sandwich panels shall have a face wythe of at least 3-1/2 in., a continuous rigid insulation layer, and a structural backup wythe of at least 3 in.
+
+## Panel thickness selection. {note}
+
+## The nominal panel thickness is recorded below for weight and connection sizing. Thin-shell cladding panels typically finish at a total of 5 in. to 7 in. including backup; sandwich panels are thicker by the insulation layer. {note}
+
+```datasheet
+label: Nominal Panel Thickness
+type: range
+min: 3.5
+max: 10
+step: 0.5
+default: 6
+unit: in.
+```
+
+## Panel self-weight. {note}
+
+## The self-weight below is used for crane sizing and gravity-connection design. Solid architectural panels typically weigh 75–90 psf; insulated sandwich panels 45–65 psf. The lighter sandwich weight is one of its advantages. {note}
+
+```datasheet
+label: Panel Self-Weight (design)
+type: range
+min: 40
+max: 100
+step: 5
+default: 80
+unit: psf
+```
+
+# Surface Finish {toc}
+
+## Finish treatment defines the architectural character. {note}
+
+## The exposed face may be left as cast, cast against a form liner for pattern or texture, or mechanically and chemically treated after stripping to expose aggregate and modulate color depth. Sandblasting, acid etching, bushhammering, retarder-wash exposed aggregate, polishing, and honing each reveal the aggregate to a different degree and read differently in raking light. Combination treatments are common. Every finish is approved only against the accepted mockup. {note}
+
+### The exposed face finish shall match the accepted finish sample and mockup in texture, aggregate exposure, and color depth.
+
+## Finish treatment. {note}
+
+## The selected finish treatment is recorded below. As-cast and light-sandblast finishes are the most common production choices; deeper exposures and polishing carry cost and lead-time premiums and are reserved for feature surfaces. {note}
+
+```datasheet
+label: Surface Finish Treatment
+type: select
+options:
+ - As-cast smooth
+ - Form liner (rubber / urethane / wood-grain / custom)
+ - Light sandblast
+ - Medium sandblast
+ - Heavy sandblast
+ - Light acid etch
+ - Medium acid etch
+ - Heavy acid etch
+ - Bushhammer
+ - Exposed aggregate (retarder wash)
+ - Polished
+ - Honed
+default: Light sandblast
+```
+
+### Where a form liner is used, the liner pattern, draft, and joint layout shall be shown on the shop drawings and shall match the accepted sample.
+
+## Color acceptance. {note}
+
+## Color shall be judged against the approved mockup under north-sky daylight at a viewing distance of about 10 ft. Judging color at arm's length or under artificial light produces rejections that would never be visible on the building. {note}
+
+### Finished color shall be accepted by comparison to the approved mockup under north-sky daylight at a viewing distance of 10 ft, and shall fall within any accepted range panels.
+
+# Tolerances {toc}
+
+## Product and erection tolerances are distinct. {note}
+
+## Product tolerances govern the dimensions of the cast unit at the plant; erection tolerances govern its installed position on the building. Joint width design must absorb both. PCI MNL-117 sets the architectural product tolerances and PCI 135-24 (and the superseded MNL-135) set erection tolerances. Specifying tolerances tighter than these without written confirmation from the producer that they are achievable drives cost premiums and RFIs — a 1/16 in. tolerance on a large panel is not a production reality. {note}
+
+### Product and erection tolerances shall conform to PCI MNL-117 and the current PCI tolerance standard unless tighter project-specific tolerances are confirmed achievable in writing by the producer.
+
+## PCI 135-24 adoption status. {note}
+
+## PCI 135-24 is a 2024 tolerance standard in public comment as of this writing. Confirm whether it has been formally adopted before citing it as mandatory; until then it is informative and MNL-135 / MNL-117 tolerances govern. {note}
+
+### Flat-panel face-dimension variation shall not exceed ±1/8 in. on panels up to 10 ft and ±3/16 in. on panels 10 ft to 20 ft.
+
+### Panel thickness shall be within ±3/16 in., and bow or warp shall not exceed 1/8 in. per 10 ft of length, with a maximum of 3/8 in.
+
+### Installed panels shall be plumb within ±1/4 in. per story, not exceeding 1 in. over the full building height.
+
+### Installed joint width shall be within ±1/4 in. of the design dimension.
+
+## Tolerance class. {note}
+
+## The applicable tolerance set is recorded below. Standard PCI architectural tolerances are the default; tighter tolerances are recorded only when the producer has confirmed them. {note}
+
+```datasheet
+label: Tolerance Class
+type: radio
+options:
+ - Standard PCI MNL-117 architectural tolerances
+ - Project-specific tighter tolerances (producer-confirmed)
+default: Standard PCI MNL-117 architectural tolerances
+```
+
+# Connections {toc}
+
+## Connection design is the leading cause of panel distress. {note}
+
+## Each panel hangs from a small number of connections that must resist gravity, wind, seismic, and thermal loads while accommodating fabrication and erection misalignment. The connection set is conventionally divided into gravity (bearing) connections, usually at the bottom of the panel, and lateral (tieback) connections that resist out-of-plane wind and seismic load and permit in-plane movement. Under-designed or under-detailed connections are the leading cause of cladding distress, which is why sealed delegated-design calculations are mandatory. {note}
+
+### Connection hardware shall be designed under delegated design and supported by calculations sealed by a professional engineer registered in the project jurisdiction.
+
+### Gravity connections shall carry the full panel self-weight; lateral connections shall resist out-of-plane wind and seismic load while permitting in-plane thermal and seismic movement.
+
+### Connections shall provide three-axis field adjustment by slotted holes, shims, or equivalent means to absorb fabrication and erection tolerance.
+
+## Why adjustability is required. {note}
+
+## With a panel fabrication tolerance and an erection tolerance both on the order of ±1/4 in., a connection with no adjustment cannot be set to the design joint line. Slotted holes, shim plates, and adjustable inserts give the erector the three-axis range needed to true the panel before the connection is locked. {note}
+
+## Connection material. {note}
+
+## Connection material follows the same corrosion logic as the embeds it joins: galvanized carbon steel in protected service, stainless in exposed exterior, and Type 316 stainless in coastal exposure. Field welding of connection assemblies is governed by AWS D1.1 and coordinated with [[sync/structural-steel-connections]] and [[sync/miscellaneous-metals]]. {note}
+
+```datasheet
+label: Connection Material
+type: radio
+options:
+ - Carbon steel, galvanized
+ - Stainless steel Type 304
+ - Stainless steel Type 316 (coastal)
+default: Carbon steel, galvanized
+```
+
+## Seismic ductility. {note}
+
+## In higher Seismic Design Categories the connections must accommodate story drift without brittle failure. The seismic category below sets the ductility and detailing demand on the connection design under ASCE 7 Chapter 13 and ACI 318. {note}
+
+```datasheet
+label: Seismic Design Category
+type: select
+options:
+ - A
+ - B
+ - C
+ - D
+ - E
+ - F
+default: C
+```
+
+### Field welds at connections shall conform to AWS D1.1 and shall be made by qualified welders.
+
+# Joints {toc}
+
+## Joint width must absorb tolerance, not fight it. {note}
+
+## The face joint between panels must be wide enough to absorb the sum of panel fabrication tolerance and erection tolerance and still leave a sealant joint that can move. A design joint that is too narrow leaves no room for the panels' real positions, forces field grinding, and overstrains the sealant. For cladding panels a minimum design joint of about 3/4 in. is typical, widening to 1 in. on taller panels. The joint width must be confirmed before bid, because it cannot be changed after the panels are cast. {note}
+
+### The design face-joint width shall be a minimum of 3/4 in. for panels up to 12 ft and 1 in. for panels 12 ft to 20 ft, and shall be confirmed before fabrication.
+
+```datasheet
+label: Design Face-Joint Width
+type: range
+min: 0.5
+max: 1.5
+step: 0.125
+default: 0.75
+unit: in.
+```
+
+### Backer rod shall be sized at approximately 1.25 times the joint width and installed to the depth required by the sealant manufacturer.
+
+## Sealant is delegated. {note}
+
+## This standard sets the joint geometry, backer-rod sizing, and bond-breaker requirement; the sealant product, conforming to ASTM C920, and its installation are selected and specified under [[sync/joint-sealants]]. Coordinating the two is essential — the joint width set here is an input the sealant standard depends on. {note}
+
+### Panel joints shall receive a bond breaker or closed-cell backer rod so the sealant bonds only to the two panel faces.
+
+## Coordination of reveals and openings. {note}
+
+## Reveal lines, window-opening locations, and joint patterns locked into the precast shop drawings must match the storefront and curtain-wall shop drawings before any panel is cast. Changes after fabrication are extremely costly, so the precast layout shall be coordinated with the glazing trades during shop-drawing review. This is the interface with [[sync/glazed-curtain-walls]] and [[sync/aluminum-entrances-and-storefronts]]. {note}
+
+### Precast panel elevations, reveals, and opening locations shall be coordinated with and confirmed against the curtain-wall, storefront, and window shop drawings before fabrication.
+
+# Installation {toc}
+
+## Erection sequence and connection. {note}
+
+## Panels are set by crane to the erection drawings, aligned within tolerance using the connection adjustment, then permanently connected and grouted. Bearing pads at gravity connections distribute load and prevent point bearing on the concrete. The erector works to the panel marks and connection assignments on the approved erection drawings. {note}
+
+### Panels shall be erected in the sequence shown on the approved erection drawings.
+
+### Panels shall be aligned to the design joint lines within the specified erection tolerance before connections are permanently fixed.
+
+### Gravity connections shall bear on the bearing pads shown on the connection details, and non-shrink grout shall be placed where detailed.
+
+### Field-welded and bolted connections shall be completed and inspected before the supporting crane is released from the panel.
+
+## Field patching. {note}
+
+## Minor surface defects and connection-pocket fills are patched in the field using a mix that matches the accepted finish in color and texture. A patch that does not match is itself a defect; patches are evaluated against the same mockup and daylight viewing standard as the panels. {note}
+
+### Field patches shall be made with a patching mix matching the accepted face finish in color and texture, and shall be evaluated against the approved mockup.
+
+### Damaged units whose defects cannot be patched to match the accepted finish shall be rejected and replaced.
+
+## Cleaning. {note}
+
+## Panels are cleaned after erection and patching to a uniform appearance. Cleaning agents and methods shall not etch, discolor, or alter the accepted finish; aggressive acids that would change the surface character are prohibited. {note}
+
+### Installed panels shall be cleaned to a uniform appearance using methods that do not alter the accepted finish.
+
+# Delivery, Storage, and Handling {toc}
+
+## Why shipping protection is specified. {note}
+
+## A finished panel face shipped face-down, stacked without edge blocking, or handled by the face develops chips and surface damage that only become visible after installation, when replacement is most expensive. A shipping, storage, and handling protection plan is required, and panels shall be supported and separated to protect the finished face throughout transport and storage. {note}
+
+### Panels shall be shipped, stored, and handled in accordance with the approved protection plan.
+
+### Finished faces shall be protected from contact, edge chipping, and staining during transport and storage by blocking, separation, and non-staining dunnage.
+
+### Lifting and handling shall use the lift points and rigging shown on the producer's handling drawings.
+
+# Warranty {toc}
+
+## Warranty scope. {note}
+
+## The producer and installer warrant the panels and their installation against defects in materials, fabrication finish, and connection workmanship. The warranty does not cover sealant, which is warranted under [[sync/joint-sealants]], nor damage from building movement beyond the design loads. {note}
+
+### The producer shall warrant the architectural precast units against defects in materials, finish, and fabrication for the warranty period stated below.
+
+### The installer shall warrant the erection and connection of the units against defective workmanship for the warranty period stated below.
+
+```datasheet
+label: Warranty Period
+type: radio
+options:
+ - 1 year
+ - 2 years
+ - 5 years
+default: 2 years
+unit: years
+```
+
+# Spare Parts {toc}
+
+## Attic stock for future repair. {note}
+
+## Because face mixes are batch-specific and color is matched to a mockup, a small stock of spare finish material and any specialty connection hardware is held so that future patching and panel repair can match the original work. The quantity is recorded below. {note}
+
+### The producer shall deliver attic stock of face-mix materials and specialty connection hardware sufficient for future patching and repair, in the quantity stated below.
+
+```datasheet
+label: Attic Stock — Face-Mix and Hardware
+type: radio
+options:
+ - None
+ - Patching kit only
+ - Patching kit plus spare connection hardware
+default: Patching kit only
+```