+---
+title: Rough Carpentry
+category: Structural
+toc_depth: 3
+description: >
+ When to use: Non-finish structural and utility wood framing and blocking. Covers dimension lumber framing (studs, plates, sills, joists, rafters, headers, ledgers); species, grade, and grade stamps under an ALSC-accredited grading agency and the National Grading Rule; design values per the AWC NDS; moisture content (S-DRY / MC19 / KD); wall, roof, and floor sheathing in plywood (DOC PS 1) and OSB (DOC PS 2) with APA span ratings and Exposure 1 bond classification; wood structural panel attachment and nailing; rooftop blocking, nailers, cant strips, curbs, and concealed wood grounds and furring; pressure-preservative-treated wood per the AWPA Use Category System and the IBC locations that require it; fire-retardant-treated (FRT) wood for interior Type III, IV, and V applications; and corrosion-resistant fasteners and metal framing connectors (joist hangers, framing anchors, post bases) compatible with treated wood and exterior service.
+ Not intended for: Finish and architectural millwork ([[syncs/architectural-wood-trim-and-paneling]]); casework ([[syncs/wood-and-laminate-casework]]); shop-fabricated structural glued-laminated timber, cross-laminated timber, and other mass timber and engineered wood products; prefabricated wood trusses; cold-formed steel framing ([[syncs/cold-formed-metal-framing]]); and concrete formwork lumber.
+---
+
+# Scope {toc}
+
+## This standard governs the materials, fabrication, and installation of rough carpentry — the non-finish structural and utility wood that frames, sheathes, blocks, and furs a building but is concealed from view or exposed only where appearance is not the controlling concern. {note}
+## Rough carpentry includes light-frame dimension lumber (studs, plates, sills, joists, rafters, and headers), wood structural panel sheathing for walls, roofs, and floors, and the miscellaneous wood that supports other work — rooftop blocking and nailers, cant strips, equipment curbs, wood grounds, furring, and concealed blocking for the attachment of finishes, fixtures, and equipment. {note}
+## The defining characteristic of rough carpentry is that it is utility wood: it is selected and graded for strength and serviceability, not for appearance, and it is normally hidden by sheathing, finishes, or roofing once construction is complete. {note}
+
+## This standard governs how the lumber, panels, fasteners, and connectors are specified, procured, treated, and installed; the contract drawings define member sizes, spacing, spans, and locations.
+
+## Member sizes, spacing, spans, and framing layout are [[drawing: as indicated on the structural drawings]].
+
+## Blocking, backing, nailer, and grounds locations are [[drawing: as indicated on the architectural and structural drawings and coordinated with the trades they support]].
+
+## Where this standard, the contract drawings, and the building code adopted by the Authority Having Jurisdiction conflict, the more stringent requirement shall govern unless the Engineer of Record or Architect of Record directs otherwise in writing.
+
+## Interface Coordination {toc}
+
+### Rough carpentry interfaces with several adjacent scopes, each governed by its own standard and coordinated here at the framing interface only. {note}
+
+### Fire blocking and draft stopping within concealed framing cavities shall be coordinated with [[syncs/firestopping]].
+
+### Rooftop blocking, nailers, cant strips, and curbs that receive membrane roofing shall be coordinated with [[syncs/membrane-roofing]].
+
+### Wood blocking and nailers that receive sheet metal flashing, copings, gravel stops, and trim shall be coordinated with [[syncs/sheet-metal-flashing-and-trim]].
+
+### Where cold-formed steel framing replaces or adjoins wood framing in the same assembly, the steel framing shall be governed by [[syncs/cold-formed-metal-framing]].
+
+### Concealed blocking and backing for the attachment of finish carpentry shall be coordinated with [[syncs/architectural-wood-trim-and-paneling]] and [[syncs/wood-and-laminate-casework]].
+
+# Referenced Standards {toc}
+
+## Materials, fabrication, and installation shall comply with the latest edition of each standard listed below as adopted by the Authority Having Jurisdiction.
+
+## Where conflicts exist between referenced standards, the more stringent requirement governs unless the Engineer of Record directs otherwise in writing.
+
+## Standards List {toc}
+
+| Standard | Title |
+|----------|-------|
+| DOC PS 20 | American Softwood Lumber Standard (U.S. Department of Commerce Voluntary Product Standard) |
+| National Grading Rule for Dimension Lumber | NGRDL — uniform visual grade definitions for dimension lumber, administered by the National Grading Rule Committee |
+| AWC NDS | National Design Specification for Wood Construction (American Wood Council), with the NDS Supplement: Design Values for Wood Construction |
+| DOC PS 1 | Structural Plywood (U.S. Department of Commerce Voluntary Product Standard) |
+| DOC PS 2 | Performance Standard for Wood Structural Panels (U.S. Department of Commerce Voluntary Product Standard) |
+| ASTM D2555 | Establishing Clear Wood Strength Values |
+| ASTM D245 | Establishing Structural Grades and Related Allowable Properties for Visually Graded Lumber |
+| AWPA U1 | Use Category System: User Specification for Treated Wood |
+| AWPA M4 | Care of Preservative-Treated Wood Products |
+| ASTM A153/A153M | Zinc Coating (Hot-Dip) on Iron and Steel Hardware |
+| ASTM A653/A653M | Steel Sheet, Zinc-Coated (Galvanized) or Zinc-Iron Alloy-Coated by the Hot-Dip Process |
+| ASTM F1667 | Driven Fasteners: Nails, Spikes, and Staples |
+| ASTM A307 | Carbon Steel Bolts, Studs, and Threaded Rod 60 000 PSI Tensile Strength |
+| ASTM F1575 | Determining Bending Yield Moment of Nails |
+| ASTM E84 | Surface Burning Characteristics of Building Materials |
+| UL 723 | Test for Surface Burning Characteristics of Building Materials |
+| ASTM D5664 | Evaluating the Effects of Fire-Retardant Treatments and Elevated Temperatures on Strength Properties of Fire-Retardant Treated Lumber |
+| ASTM D5516 | Evaluating the Flexural Properties of Fire-Retardant Treated Softwood Plywood Exposed to Elevated Temperatures |
+| ASTM D6841 | Calculating Design Value Treatment Adjustment Factors for Fire-Retardant-Treated Lumber |
+| ICC-ES AC257 | Acceptance Criteria for Corrosion-Resistant Fasteners and Evaluation of Corrosion Effects of Wood Treatment Chemicals |
+| IBC Chapter 23 | International Building Code, Chapter 23 (Wood) — current edition adopted by jurisdiction |
+| AWC WFCM | Wood Frame Construction Manual for One- and Two-Family Dwellings (where applicable) |
+
+### Lumber design values published in the NDS Supplement are tabulated by species or species group, commercial grade, and size classification; the design value used in calculation must match the grade and species actually grade-stamped on the delivered material. {note}
+### DOC PS 1 covers structural plywood and DOC PS 2 covers the broader family of wood structural panels including oriented strand board (OSB); APA span-rated panels are produced under one or both of these product standards. {note}
+### AWPA U1 organizes preservative treatment by Use Category (UC1 through UC5) according to the exposure and biodeterioration hazard the wood will face in service, which is the basis for both the IBC requirements and the procurement of treated material. {note}
+
+# Submittals {toc}
+
+## Action Submittals {toc}
+
+### The Contractor shall submit the following for review by the Architect of Record and the Engineer of Record prior to procurement and installation:
+
+- Product data and grade-mark facsimiles for each species, grade, and size classification of dimension lumber to be supplied, identifying the ALSC-accredited grading agency
+- Product data for wood structural panels, identifying the product standard (DOC PS 1 or DOC PS 2), the APA span rating, the bond classification (Exposure 1 or Exterior), and the thickness for each sheathing application
+- Product data and treatment certificates for pressure-preservative-treated wood, stating the preservative, the AWPA Use Category, the retention, and the treatment standard, with confirmation of post-treatment kiln drying where required
+- Product data and evaluation report listings for fire-retardant-treated (FRT) wood, stating the flame-spread index, the smoke-developed index, the interior Type A or Type B classification, and the published strength-adjustment and design-value treatment factors
+- Product data and current evaluation reports (ICC-ES or equivalent) for metal framing connectors — joist hangers, framing anchors, hold-downs, post bases, and post caps — including the coating designation and allowable loads
+- Product data for fasteners — nails, screws, lag screws, bolts, and powder-actuated fasteners — including material, coating, and dimensions
+- Material certificates for preservative-treated and fire-retardant-treated wood confirming compliance with the specified treatment standard and retention
+
+```datasheet
+label: Action Submittals Required
+type: checkbox
+options:
+ - "Dimension lumber product data and grade-mark facsimiles (species, grade, agency)"
+ - "Wood structural panel product data (PS 1 / PS 2, span rating, Exposure 1)"
+ - "Preservative-treated wood product data and treatment certificates (AWPA UC, retention)"
+ - "Fire-retardant-treated wood product data and evaluation report (flame spread, strength factors)"
+ - "Metal framing connector product data and evaluation reports (coating, allowable loads)"
+ - "Fastener product data (nails, screws, lag screws, bolts, PAFs)"
+ - "Treatment material certificates (preservative and FRT)"
+default: "Dimension lumber product data and grade-mark facsimiles (species, grade, agency)"
+```
+
+### Grade-mark facsimiles shall identify the grading agency, the assigned grade, the species or species group, the seasoning condition, and the mill identification so that the delivered material can be verified against the design values used in the structural design.
+
+### Treatment certificates for preservative-treated wood shall state the preservative chemical, the AWPA Use Category, the retention in pounds per cubic foot, and the AWPA treatment standard to which the wood was treated.
+
+### Evaluation reports for fire-retardant-treated wood shall be submitted because the strength of FRT wood is reduced by the treatment, and the published design-value treatment factors govern the structural use of the material. {note}
+
+### Evaluation reports for metal framing connectors shall be current and shall confirm both the allowable loads and the coating designation required for the service condition.
+
+## Informational Submittals {toc}
+
+### The Contractor shall submit the following for information:
+
+- Manufacturer's installation instructions for metal framing connectors, including required fastener type, quantity, and placement for the published allowable loads
+- Manufacturer's recommendations for fasteners and connectors used in contact with the specified preservative-treated and fire-retardant-treated wood
+
+```datasheet
+label: Informational Submittals Required
+type: checkbox
+options:
+ - "Connector manufacturer installation instructions (fastener type, quantity, placement)"
+ - "Treated-wood fastener and connector compatibility recommendations"
+default: ["Connector manufacturer installation instructions (fastener type, quantity, placement)", "Treated-wood fastener and connector compatibility recommendations"]
+```
+
+# Quality Assurance {toc}
+
+## Grade Marking {toc}
+
+### All lumber and wood structural panels shall be marked by an inspection agency accredited by the American Lumber Standard Committee (ALSC) under the U.S. Department of Commerce softwood lumber standard PS 20. {note}
+### The ALSC accreditation, the National Grading Rule, and the grade stamp together make a piece of dimension lumber a known, design-value-bearing structural element rather than an anonymous board; specifying a grade and species without requiring the stamp leaves the actual strength of the delivered material unverifiable. {note}
+
+```datasheet
+label: Lumber Grading Agency
+type: select
+options:
+ - "Any ALSC-accredited agency for the species supplied"
+ - "Western Wood Products Association (WWPA)"
+ - "Southern Pine Inspection Bureau (SPIB)"
+ - "West Coast Lumber Inspection Bureau (WCLIB)"
+ - "Northeastern Lumber Manufacturers Association (NELMA)"
+ - "National Lumber Grades Authority (NLGA)"
+default: "Any ALSC-accredited agency for the species supplied"
+```
+
+### Each piece of dimension lumber shall bear the grade mark of an ALSC-accredited grading agency identifying the grade, the species or species group, the seasoning condition, and the mill.
+
+### Each wood structural panel shall bear the trademark of an approved testing and inspection agency identifying the product standard, the span rating, the bond classification, and the panel grade.
+
+### Where lumber is cut so that the grade mark is removed from a member that remains in a structural application, the absence of the mark shall not by itself be cause for rejection, provided the member can be identified to a marked piece of the same lot or is re-marked by a qualified inspector. {note}
+
+## Material Inspection {toc}
+
+### Lumber and panels shall be inspected on delivery for grade mark, species, moisture condition, and physical damage. {note}
+
+### Warped, split, decayed, or insect-damaged material shall not be installed.
+
+### Lumber with wane, splits, or checks exceeding the limits of the specified grade shall be rejected.
+
+### Material that has been wetted and shows fungal staining or surface mold shall be set aside, dried, and inspected before installation; visibly decayed material shall be rejected.
+
+## Pre-Installation Coordination {toc}
+
+### Before rough carpentry that supports other work is installed, the Contractor shall coordinate the location, size, and attachment of blocking, backing, nailers, and grounds with the trades whose work attaches to them.
+
+### Blocking and backing for wall-hung equipment, handrails, grab bars, casework, and fixtures shall be located from the approved shop drawings and mounting heights of the supported work, not from rough carpentry alone, so the attachment points fall within the installed blocking. {note}
+
+# Environmental and Service Conditions {toc}
+
+## Service Condition and Decay Hazard {toc}
+
+### The service environment of each rough carpentry member shall determine whether untreated, preservative-treated, or fire-retardant-treated wood is required, and the coating class of the fasteners and connectors that contact it. {note}
+
+```datasheet
+label: Member Service Condition
+type: select
+options:
+ - "Interior, dry — conditioned, concealed framing"
+ - "Interior, intermittently wet — within the building but subject to moisture"
+ - "In contact with concrete or masonry — sills, plates, sleepers, furring on exterior walls"
+ - "Exterior, above ground — protected from sustained wetting, not ground contact"
+ - "Exterior, ground contact or persistently wet"
+default: "Interior, dry — conditioned, concealed framing"
+```
+
+### Interior dry framing concealed within a conditioned building envelope may be untreated lumber where decay and termite hazards are not present and the code does not require treatment.
+
+### Wood in contact with concrete or masonry, wood exposed to weather, and wood subject to sustained moisture shall be pressure-preservative-treated to the applicable AWPA Use Category, or shall be of a naturally durable species where the code permits.
+
+### Untreated wood placed in contact with concrete, masonry, or the ground is one of the most common and most consequential rough carpentry errors, because the resulting decay is concealed within the assembly until structural capacity is lost; the cost of treated material at these locations is negligible against the cost of the failure it prevents. {note}
+
+## Moisture Content {toc}
+
+### Dimension lumber shall be supplied seasoned (dried) to a maximum moisture content appropriate to the application, because lumber installed wet shrinks as it dries in service, opening connections, loosening fasteners, and causing dimensional change in the framed assembly. {note}
+
+```datasheet
+label: Maximum Moisture Content at Installation — Dimension Lumber
+type: radio
+options:
+ - "19 percent (S-DRY / KD / MC19) — standard framing lumber"
+ - "15 percent (MC15 / KD-15) — where reduced shrinkage and movement are required"
+default: "19 percent (S-DRY / KD / MC19) — standard framing lumber"
+```
+
+### Dimension lumber 2 in. nominal and less in thickness shall be surfaced dry or kiln dried to a maximum moisture content of 19 percent, identified by the grade-stamp marking S-DRY, KD, or MC19.
+
+### Where reduced shrinkage is required — at framing supporting brittle finishes, at tall stacked-stud walls, or where the design so states — lumber shall be kiln dried to a maximum moisture content of 15 percent (MC15 or KD-15).
+
+### Lumber that has regained moisture in storage above the specified maximum shall be re-dried or rejected before installation. {note}
+
+## Storage and Handling {toc}
+
+### Lumber and wood structural panels shall be delivered and stored above ground on level supports, protected from weather, and covered with a ventilated covering that excludes rain and snow while permitting air circulation.
+
+### Material shall not be stored in direct contact with the ground or on a surface that allows water to pool beneath the stack.
+
+### Panels and lumber wrapped in moisture-trapping film shall have the film loosened or removed promptly on delivery, because film that traps condensation against bundled material raises the moisture content and promotes mold and warping. {note}
+
+### Preservative-treated and fire-retardant-treated wood shall be stored in accordance with AWPA M4 and the treater's instructions to protect the treatment and limit re-wetting.
+
+# Dimension Lumber {toc}
+
+## Species and Grade {toc}
+
+### Dimension lumber shall be of the species or species group and the visual stress grade required to provide the design values used in the structural design, as established under the National Grading Rule and tabulated in the NDS Supplement. {note}
+### The same nominal size in a stronger species or a higher grade carries a higher design value; substituting a weaker species or a lower grade than the structural design assumed reduces the capacity of the framing even though the member looks identical. {note}
+
+```datasheet
+label: Framing Lumber Species Group
+type: select
+drawing_ref: "structural drawings"
+options:
+ - "Douglas Fir-Larch"
+ - "Southern Pine"
+ - "Hem-Fir"
+ - "Spruce-Pine-Fir (SPF)"
+ - "Spruce-Pine-Fir (South)"
+default: deferred
+```
+
+```datasheet
+label: Dimension Lumber Grade — Framing
+type: select
+options:
+ - "Stud grade (stud-wall framing)"
+ - "No. 2 (general framing — joists, rafters, plates)"
+ - "No. 1 (higher design values where required)"
+ - "Select Structural (highest visual grade)"
+default: "No. 2 (general framing — joists, rafters, plates)"
+```
+
+### Dimension lumber shall be the species or species group indicated on the structural drawings.
+
+### Stud-grade lumber shall be used for stud-wall framing within the height limits for which stud grade is tabulated; No. 2 grade shall be used for general framing including joists, rafters, headers, and plates unless a higher grade is shown.
+
+### The design values for the supplied species and grade shall equal or exceed the design values used in the structural design; substitution of a different species or grade shall not be made without the Engineer of Record's written approval. {note}
+
+### Light Framing Size Classification {toc}
+
+#### Dimension lumber is graded in size classifications — Structural Light Framing and Stud (2 in. to 4 in. thick, 2 in. to 4 in. wide), and Structural Joists and Planks (2 in. to 4 in. thick, 5 in. and wider) — each with its own grade design values; the design value for a 2x4 stud differs from that of a 2x10 joist of the same grade and species. {note}
+
+#### Members shall be supplied in the size classification that matches their structural use so that the tabulated design value applies.
+
+## Plates, Sills, and Sleepers {toc}
+
+### Sill plates, sole plates, and sleepers bearing on concrete or masonry shall be pressure-preservative-treated wood, or naturally durable wood where the code permits, because these members sit at the interface where moisture migrates from the concrete into the wood. {note}
+
+```datasheet
+label: Sill / Sole Plate on Concrete or Masonry
+type: radio
+options:
+ - "Preservative-treated, AWPA UC2 (interior, dry) or UC3B (exterior/damp) per location"
+ - "Naturally durable species (where permitted by code)"
+default: "Preservative-treated, AWPA UC2 (interior, dry) or UC3B (exterior/damp) per location"
+```
+
+### Sill plates and sole plates in direct contact with concrete or masonry that is in contact with the ground shall be preservative-treated or naturally durable wood, as required by IBC Section 2304.12.
+
+### A sill sealer or gasket shall be installed between the sill plate and the top of foundation concrete or masonry to close the air gap and limit moisture transfer.
+
+```datasheet
+label: Sill Sealer / Gasket Under Plates on Concrete
+type: radio
+options:
+ - "Closed-cell foam sill sealer (standard air and moisture gasket)"
+ - "Capillary break membrane / through-wall flashing where shown"
+ - "Not required (interior non-rated, no air-barrier continuity at this line)"
+default: "Closed-cell foam sill sealer (standard air and moisture gasket)"
+```
+
+### Anchorage of sill and sole plates to the foundation shall be [[drawing: as indicated on the structural drawings]].
+
+## Blocking, Backing, Nailers, and Furring {toc}
+
+### Blocking, backing, nailers, grounds, and furring are the utility members of rough carpentry: they fill cavities, provide attachment for finishes and equipment, and create surfaces and offsets for other work; they are sized and located to serve the work they support rather than to carry primary structural loads. {note}
+
+### Concealed blocking and backing shall be provided wherever finishes, fixtures, casework, handrails, grab bars, equipment, or accessories require solid attachment that the framing alone does not provide.
+
+### Wood furring and grounds shall be provided where finishes require a continuous nailing surface or a controlled offset from the structure.
+
+### Blocking and nailers in contact with concrete, masonry, or exterior assemblies, and all rooftop wood, shall be preservative-treated.
+
+# Rooftop Blocking, Nailers, Cant Strips, and Curbs {toc}
+
+## Wood that is built into the roofing assembly — perimeter nailers, blocking at penetrations and equipment, cant strips at base flashings, and equipment curbs — shall be preservative-treated, because it is concealed within the roof, subject to condensation and incidental leakage, and difficult and disruptive to replace. {note}
+
+## Rooftop wood blocking, nailers, cant strips, and curbs shall be preservative-treated to AWPA Use Category UC3B (exterior, above ground) at minimum.
+
+## Rooftop nailers shall be anchored to the structural deck or to the structure to resist the roofing system's design wind uplift, with anchorage [[drawing: as indicated on the roof framing and roofing drawings]].
+
+```datasheet
+label: Rooftop Nailer Anchorage to Deck
+type: select
+options:
+ - "Mechanical fasteners to structural concrete or steel deck per roofing wind-uplift design"
+ - "Through-bolted to structural members"
+ - "Powder-actuated fasteners to structural deck (where permitted by uplift design)"
+default: "Mechanical fasteners to structural concrete or steel deck per roofing wind-uplift design"
+```
+
+## The thickness of rooftop nailers shall match the thickness of the adjacent insulation so that the nailer surface is flush with the insulation to receive the membrane and flashing.
+
+```datasheet
+label: Wood Nailer Thickness Matches Insulation
+type: radio
+options:
+ - "Nailers furnished in thicknesses matching the roof insulation lifts (flush surface)"
+ - "Single-thickness nailers (low-slope, thin insulation only)"
+default: "Nailers furnished in thicknesses matching the roof insulation lifts (flush surface)"
+```
+
+## Cant strips at the base of walls, curbs, and parapets shall be installed to provide the angled transition the membrane base flashing requires, and shall be coordinated with [[syncs/membrane-roofing]].
+
+## Wood nailers and blocking that receive sheet metal copings, gravel stops, and edge metal shall be coordinated with [[syncs/sheet-metal-flashing-and-trim]] for size, attachment, and continuity.
+
+# Wood Structural Panels {toc}
+
+## Panel Standards and Span Rating {toc}
+
+### Wood structural panels for wall, roof, and floor sheathing shall be plywood produced under DOC PS 1 or wood structural panels (including OSB) produced under DOC PS 2, marked with the trademark of an approved inspection agency. {note}
+### The APA span rating marked on a panel is the controlling specification for sheathing: it states the maximum on-center spacing of supports the panel may span, which is matched to the framing spacing on the drawings, so the span rating — not the thickness alone — is what makes a panel suitable for a given application. {note}
+
+```datasheet
+label: Wood Structural Panel Product Standard
+type: radio
+options:
+ - "Either PS 1 (plywood) or PS 2 (OSB or plywood) at the supplier's option"
+ - "PS 1 structural plywood only"
+ - "PS 2 wood structural panel (OSB or plywood)"
+default: "Either PS 1 (plywood) or PS 2 (OSB or plywood) at the supplier's option"
+```
+
+### Panels shall bear an APA or equivalent span rating equal to or greater than the framing spacing on which they are installed.
+
+### The panel thickness and span rating for each application shall match the framing spacing shown on the structural drawings; substitution of a lower span rating shall not be made.
+
+## Bond Classification {toc}
+
+### The bond classification of a wood structural panel describes the moisture resistance of the adhesive bond between plies or strands, and shall be selected for the moisture exposure the panel will see in service and during construction. {note}
+### Exposure 1 panels use an exterior (waterproof) adhesive and tolerate the wetting that normally occurs during construction before the building is closed in, but are not intended for long-term weather exposure; Exterior-classified panels tolerate permanent exposure to weather. {note}
+
+```datasheet
+label: Panel Bond Classification
+type: radio
+options:
+ - "Exposure 1 (waterproof bond; tolerates construction moisture)"
+ - "Exterior (permanent weather exposure)"
+default: "Exposure 1 (waterproof bond; tolerates construction moisture)"
+```
+
+### Wall, roof, and floor sheathing concealed within the assembly shall be Exposure 1 bond classification at minimum.
+
+### Panels subject to permanent exposure to weather shall be Exterior bond classification.
+
+### Exposure 1 is the prevailing specification for concealed structural sheathing in U.S. construction; it is sometimes loosely called "CDX," but the correct specification is the bond classification and span rating, not a veneer-grade nickname. {note}
+
+## Sheathing Application {toc}
+
+```datasheet
+label: Wall Sheathing Nominal Thickness
+type: select
+unit: in.
+drawing_ref: "structural drawings"
+options:
+ - "7/16 in."
+ - "15/32 in."
+ - "1/2 in."
+ - "19/32 in."
+ - "5/8 in."
+default: deferred
+```
+
+```datasheet
+label: Roof Sheathing Nominal Thickness
+type: select
+unit: in.
+drawing_ref: "structural drawings"
+options:
+ - "15/32 in."
+ - "1/2 in."
+ - "19/32 in."
+ - "5/8 in."
+ - "23/32 in."
+ - "3/4 in."
+default: deferred
+```
+
+```datasheet
+label: Floor Sheathing (Subfloor) Nominal Thickness
+type: select
+unit: in.
+drawing_ref: "structural drawings"
+options:
+ - "19/32 in."
+ - "23/32 in."
+ - "3/4 in."
+ - "7/8 in."
+ - "1-1/8 in."
+default: deferred
+```
+
+```datasheet
+label: Floor Sheathing Edge Profile
+type: radio
+options:
+ - "Tongue-and-groove edges (standard subfloor; controls edge differential movement)"
+ - "Square edge with solid blocking at unsupported panel edges"
+default: "Tongue-and-groove edges (standard subfloor; controls edge differential movement)"
+```
+
+### Sheathing panels shall be installed with the long dimension or strength axis perpendicular to the supports unless the design and the panel span rating permit otherwise.
+
+### Panels shall be installed with a gap at panel edges and ends as recommended by the panel manufacturer to accommodate expansion from moisture, because panels butted tight buckle when they take on construction moisture. {note}
+
+### End joints of sheathing panels shall be staggered between adjacent rows where required to develop diaphragm action shown on the structural drawings.
+
+# Treated Wood {toc}
+
+## Preservative-Treated Wood {toc}
+
+### Pressure-preservative-treated wood shall be treated to the AWPA Use Category that matches the exposure and biodeterioration hazard of its location in the building, as specified in AWPA U1. {note}
+### The Use Category, not the preservative brand, is the procurement specification: UC2 for interior wood subject to dampness, UC3B for exterior wood above ground exposed to weather, UC4A for ground contact and general use, and higher categories for severe and structural ground-contact conditions. {note}
+
+```datasheet
+label: Preservative Treatment Use Category (AWPA U1)
+type: select
+options:
+ - "UC2 — interior, occasional dampness (sill/sole plates on interior slabs)"
+ - "UC3B — exterior, above ground, exposed (rooftop wood, exterior wall plates, exposed framing)"
+ - "UC4A — ground contact, general use"
+ - "UC4B — ground contact, heavy duty / critical"
+default: "UC3B — exterior, above ground, exposed (rooftop wood, exterior wall plates, exposed framing)"
+```
+
+```datasheet
+label: Waterborne Preservative
+type: select
+options:
+ - "Alkaline copper quaternary (ACQ)"
+ - "Copper azole (CA-C)"
+ - "Either ACQ or CA-C at supplier's option (most common above-ground/ground-contact)"
+ - "Micronized copper formulation (MCA / MCQ)"
+default: "Either ACQ or CA-C at supplier's option (most common above-ground/ground-contact)"
+```
+
+### Preservative-treated wood shall be treated by a pressure process to the retention required by AWPA U1 for the specified Use Category.
+
+### Treated wood shall be supplied with the treater's end tag or stamp identifying the preservative, the Use Category or retention, and the treatment standard.
+
+### Lumber that is cut, drilled, or notched after treatment shall have the cut surfaces field-treated with a compatible preservative in accordance with AWPA M4, because the pressure treatment does not fully penetrate to the core of many species and a field cut exposes untreated wood. {note}
+
+### Preservative-treated wood used in enclosed or occupied conditions shall be kiln dried after treatment (KDAT) where dimensional stability or low moisture content is required, because waterborne-treated wood leaves the treating cylinder saturated. {note}
+
+## Fire-Retardant-Treated Wood {toc}
+
+### Fire-retardant-treated (FRT) wood shall be used where the building code permits combustible framing or blocking within fire-resistance-rated or noncombustible-construction conditions — typically interior framing, blocking, and roof sheathing in Type III, IV, and V construction. {note}
+### FRT wood is pressure-impregnated with fire-retardant chemicals that reduce surface flame spread; it is a distinct product from preservative-treated wood and addresses fire performance, not decay, so the two treatments are not interchangeable. {note}
+
+```datasheet
+label: Fire-Retardant-Treated Wood Application
+type: radio
+options:
+ - "Not used — no FRT wood required on this project"
+ - "Interior FRT framing and blocking (Type III / IV / V interior applications)"
+ - "Interior FRT roof sheathing and roof framing (where required by construction type)"
+default: "Not used — no FRT wood required on this project"
+```
+
+```datasheet
+label: FRT Interior Exposure Classification
+type: radio
+options:
+ - "Interior Type A (low-hygroscopic; standard interior conditioned use)"
+ - "Interior Type B (resists higher-humidity interior conditions)"
+default: "Interior Type A (low-hygroscopic; standard interior conditioned use)"
+```
+
+### Fire-retardant-treated wood shall have a flame-spread index of 25 or less when tested per ASTM E84 or UL 723, with no evidence of significant progressive combustion when the test is continued for an additional 20 minutes, and a smoke-developed index not exceeding 450.
+
+### FRT wood used as interior framing shall be Interior Type A or Type B as required by the interior humidity condition, and shall not be used in exterior or weather-exposed applications.
+
+### Fire-retardant-treated wood shall not be used in exterior applications or where exposed to weather, because the fire-retardant chemicals are hygroscopic and leach or degrade under exterior moisture exposure. {note}
+
+### Design values for FRT lumber and plywood shall be reduced by the strength-adjustment factors published in the product's evaluation report, derived from ASTM D5664 (lumber) and ASTM D5516 (plywood) elevated-temperature testing and ASTM D6841, and the reduced design values shall be used in the structural design of FRT members.
+
+### FRT roof sheathing and roof framing carry an additional roof-temperature strength reduction because the chemicals continue to degrade strength at the elevated temperatures reached under roofing in service; the roof-application strength-adjustment factors from the evaluation report shall govern these members. {note}
+
+### Fasteners and connectors in contact with FRT wood shall be selected per the FRT manufacturer's recommendations, because some fire-retardant chemistries are corrosive to standard fasteners.
+
+# Fasteners and Connectors {toc}
+
+## Fastener Materials and Coatings {toc}
+
+### Fasteners shall be selected for the corrosion environment of their location and for compatibility with the wood they contact, because the waterborne copper-based preservatives now used for treated wood are substantially more corrosive to plain and lightly coated steel than the older preservatives they replaced. {note}
+### Standard bright or electro-zinc-plated fasteners corrode rapidly in contact with ACQ- and CA-treated wood and in exterior service; using them where a hot-dip galvanized or stainless fastener is required produces rust staining, loss of fastener capacity, and eventual connection failure. {note}
+
+```datasheet
+label: Nail and Screw Coating
+type: select
+options:
+ - "Bright / uncoated — interior, dry, untreated wood only"
+ - "Hot-dip galvanized, ASTM A153 Class D — exterior, and contact with preservative-treated wood"
+ - "Type 304 stainless steel — high-corrosion exterior and severe service"
+ - "Type 316 stainless steel — coastal / chloride exposure and persistent wetting"
+default: "Hot-dip galvanized, ASTM A153 Class D — exterior, and contact with preservative-treated wood"
+```
+
+### Nails, spikes, and staples shall conform to ASTM F1667 for type, size, and material.
+
+### Fasteners in contact with preservative-treated wood and fasteners in exterior service shall be hot-dip galvanized conforming to ASTM A153/A153M, stainless steel, silicon bronze, or copper, as required by IBC Section 2304.10.
+
+### Stainless steel fasteners shall be used in coastal and chloride-exposed locations, in continuously wet service, and where the treated-wood or fastener manufacturer's recommendations require stainless steel for the preservative and retention used.
+
+### Bright (uncoated) fasteners may be used only for interior, dry, untreated wood framing not exposed to moisture.
+
+## Bolts and Lag Screws {toc}
+
+### Bolts shall conform to ASTM A307 and lag screws to the applicable ANSI/ASME dimensional standard, of a coating class matching the service condition and the wood they connect. {note}
+
+```datasheet
+label: Bolt and Lag Screw Coating
+type: radio
+options:
+ - "Plain (interior, dry, untreated wood)"
+ - "Hot-dip galvanized, ASTM A153 (exterior and preservative-treated wood)"
+ - "Stainless steel (coastal / chloride / continuously wet)"
+default: "Hot-dip galvanized, ASTM A153 (exterior and preservative-treated wood)"
+```
+
+### Bolted connections shall use a steel washer under the head and the nut bearing on wood, sized to distribute the load without crushing the wood.
+
+### Bolt and lag screw holes shall be drilled to the diameters required by the NDS for the lead hole and the shank so the connection develops its design capacity without splitting the member.
+
+## Metal Framing Connectors {toc}
+
+### Metal framing connectors — joist hangers, framing anchors, hold-downs, post bases, and post caps — shall be the type and model that carry the connection loads shown on the structural drawings, selected from a current evaluation report establishing their allowable loads. {note}
+### A connector achieves its published allowable load only when it is fastened with the specific fastener type, size, and quantity the evaluation report requires; substituting fewer or different fasteners voids the rated capacity even though the connector is installed. {note}
+
+```datasheet
+label: Connector Coating Designation
+type: select
+options:
+ - "ASTM A653 G90 galvanized — interior dry"
+ - "ASTM A653 G185 galvanized — exterior and contact with preservative-treated wood"
+ - "Type 304 stainless steel — high-corrosion exterior"
+ - "Type 316 stainless steel — coastal / chloride exposure"
+default: "ASTM A653 G185 galvanized — exterior and contact with preservative-treated wood"
+```
+
+```datasheet
+label: Connector Allowable Load Basis
+type: radio
+options:
+ - "Per current ICC-ES (or equivalent) evaluation report for the connector"
+ - "Per project-specific connection design by the Engineer of Record"
+default: "Per current ICC-ES (or equivalent) evaluation report for the connector"
+```
+
+### Connectors in contact with preservative-treated wood and connectors in exterior service shall have a galvanized coating of ASTM A653 G185 minimum, or shall be stainless steel, in accordance with IBC Section 2304.10.
+
+### Connectors shall be installed with the full quantity and type of fasteners specified in the connector evaluation report to develop the published allowable load.
+
+### Joist hangers shall be sized so the joist seats fully on the hanger seat and the hanger height matches the joist depth, and shall not be field-modified by bending or cutting in a way the evaluation report does not permit.
+
+### Post bases shall hold the post base above the bearing surface to provide a drainage gap and prevent the end grain of the post from sitting in standing water. {note}
+
+# Installation {toc}
+
+## General Framing {toc}
+
+### Framing shall be installed plumb, level, and true to line, with members spaced and located as shown on the structural drawings.
+
+### Members shall be cut square and installed in full bearing on their supports; members shall not be cut short and shimmed to length.
+
+### Notching and boring of structural members shall not exceed the limits established by the building code and the NDS for the member size and location, because over-cut members lose flexural and shear capacity at the cut. {note}
+
+### Multiple-member built-up beams and headers shall be fastened together in the nailing or bolting pattern shown on the structural drawings so the members act together.
+
+### Bearing of joists, rafters, and beams on their supports shall provide the minimum bearing length required by the design.
+
+## Wall Framing {toc}
+
+### Stud walls shall be framed with continuous bottom plates and the number of top plates shown on the drawings, with studs in full bearing between plates.
+
+### Top plates of bearing and exterior walls shall be lapped and nailed at corners and intersections to tie the walls together, as shown on the structural drawings.
+
+### Openings in stud walls shall be framed with headers, king studs, jack (trimmer) studs, and cripples sized and arranged per the structural drawings.
+
+### Studs shall not be cut, notched, or bored beyond the limits permitted for the wall type, and damaged or over-cut studs shall be reinforced or replaced. {note}
+
+## Fire Blocking and Draft Stopping {toc}
+
+### Fire blocking shall be installed in concealed framing spaces to cut off the concealed draft path at the locations required by the building code, and shall be coordinated with [[syncs/firestopping]].
+
+### Fire blocking shall be installed at the locations [[drawing: as indicated on the architectural drawings and required by the adopted building code]].
+
+### Fire blocking material shall be the lumber, panel, or approved material required by the code for the location, fit to fill the concealed space.
+
+## Sheathing Installation {toc}
+
+### Wood structural panel sheathing shall be installed with the strength axis across the supports, fastened at the panel edges and at intermediate supports with the nail size and spacing shown on the structural drawings.
+
+```datasheet
+label: Sheathing Edge Nail Spacing
+type: select
+unit: in. o.c.
+drawing_ref: "structural drawings"
+options:
+ - "6 in. on center (typical field sheathing)"
+ - "4 in. on center (moderate shear)"
+ - "3 in. on center (high shear walls / diaphragms)"
+ - "2 in. on center (highest shear)"
+default: deferred
+```
+
+```datasheet
+label: Sheathing Field (Intermediate) Nail Spacing
+type: select
+unit: in. o.c.
+options:
+ - "12 in. on center (typical)"
+ - "6 in. on center (where shown for diaphragm)"
+default: "12 in. on center (typical)"
+```
+
+### Sheathing nails shall be driven flush with the panel surface and shall not be overdriven, because an overdriven nail that breaks the panel face veneer or strand surface loses a large fraction of its shear capacity. {note}
+
+### Edge distance from the panel edge to the centerline of the fastener shall be maintained at the minimum shown on the structural drawings so the fastener does not tear out at the panel edge.
+
+### Panel edges that are not supported by framing and that require support for shear transfer shall be backed with solid blocking where the structural drawings call for blocked diaphragms or shear walls.
+
+### Panel-to-panel gaps at edges and ends shall be maintained per the panel manufacturer's recommendation to allow for moisture expansion.
+
+## Connector Installation {toc}
+
+### Metal framing connectors shall be installed in the locations shown on the structural drawings, fastened with the full fastener schedule from the connector evaluation report.
+
+### Hold-downs and anchor connectors in the lateral force-resisting system shall be installed and tightened per the design, and shall be inspected before the framing is concealed where special inspection is required.
+
+### Fasteners into connectors in contact with preservative-treated or fire-retardant-treated wood shall be of the coating class required for that contact condition.
+
+## Field Treatment and Protection {toc}
+
+### Field cuts, holes, and notches in preservative-treated wood shall be brush- or spray-treated with a compatible preservative in accordance with AWPA M4 before the cut surface is concealed.
+
+### Damage to the galvanized coating on connectors and fasteners shall be repaired with a zinc-rich coating, or the damaged item shall be replaced.
+
+# Testing and Inspection {toc}
+
+## Visual Inspection {toc}
+
+### Rough carpentry shall be visually inspected before it is concealed by sheathing, finishes, or roofing. {note}
+
+### Inspection shall verify that members are the species, grade, and size shown on the drawings; that framing is plumb, level, and to line; that spacing and bearing meet the design; that treated wood is used at all required locations; and that fasteners and connectors are of the required type, coating, and quantity.
+
+### Sheathing inspection shall verify panel span rating and bond classification, strength-axis orientation, edge and field nail spacing, that nails are not overdriven, that edge distance and edge gaps are maintained, and that blocking is installed where blocked diaphragms or shear walls are required.
+
+## Special Inspection {toc}
+
+```datasheet
+label: Special Inspection of Wood Framing (Seismic / Wind LFRS)
+type: radio
+options:
+ - "Required — wood shear walls and diaphragms in the designated lateral force-resisting system (per IBC Chapter 17)"
+ - "Not required — framing not part of a designated LFRS requiring special inspection (verify with AHJ)"
+default: "Required — wood shear walls and diaphragms in the designated lateral force-resisting system (per IBC Chapter 17)"
+```
+
+### Where the adopted building code requires special inspection of wood framing, the Owner shall retain a special inspector approved by the Authority Having Jurisdiction.
+
+### Special inspection of designated wood shear walls and diaphragms shall verify panel grade and thickness, nail size, edge and field nail spacing, that nails are not overdriven, blocking, and the connectors and hold-downs of the lateral force-resisting system, before the work is concealed.
+
+### The shear capacity of a wood shear wall or diaphragm is highly sensitive to the nail size and spacing and to overdriven nails; field deviation from the nailing schedule is not permitted. {note}
+
+## Moisture Content Verification {toc}
+
+### Where reduced moisture content is specified, the moisture content of delivered lumber may be verified with a moisture meter, and material exceeding the specified maximum shall be re-dried or rejected.
+
+# Delivery, Storage, and Handling {toc}
+
+```datasheet
+label: Site Storage Requirements
+type: checkbox
+options:
+ - "Store on level supports elevated above ground; no direct ground contact"
+ - "Cover to exclude rain and snow while permitting air circulation"
+ - "Loosen or remove moisture-trapping film promptly on delivery"
+ - "Separate by species, grade, and treatment to prevent installation errors"
+ - "Store treated wood per AWPA M4 and the treater's instructions"
+default: "Store on level supports elevated above ground; no direct ground contact"
+```
+
+## Lumber and panels shall be delivered bundled and marked, and shall be unloaded and handled to prevent breakage, splitting, and surface damage.
+
+## Material shall be stored above the ground on level supports and covered with a ventilated weather covering.
+
+## Treated wood shall be handled and stored to protect the treatment, and field-cut surfaces of preservative-treated wood shall be re-treated before the wood is installed.
+
+## Material that has been wetted, mold-stained, or damaged in storage shall be dried and inspected, and rejected where decay, distortion, or damage exceeds the limits of the specified grade.
+
+# Warranty {toc}
+
+```datasheet
+label: Rough Carpentry Warranty Period
+type: select
+options:
+ - "1 year from substantial completion"
+ - "2 years from substantial completion"
+default: "1 year from substantial completion"
+```
+
+## The Contractor shall warrant the rough carpentry against defects in materials and workmanship for the project warranty period beginning at substantial completion.
+
+## Warranty obligations shall include correction of framing that is out of plumb, level, or line beyond tolerance; loose, missing, or incorrectly coated fasteners and connectors; sheathing nailing deficiencies; and decay or corrosion attributable to the use of untreated wood or incompatible fasteners where treated wood or corrosion-resistant fasteners were required.
+
+## The warranty shall not relieve the Contractor of liability for concealed non-conforming work, including the use of untreated wood at locations requiring treatment, discovered after the warranty period.