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SynC · Editorial revision

Finish Carpentry

Revision3
EditedOct 12, 2026
StatusCurrent
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View changes in this revision   Revision history

Current revision. This is editorial revision 3, the current text of this standard. Read it on the standard's page.

SynC Standards Team — Specifier (Platform Standards) ✓ OfficialDiscloses employment SynC (SynC Platform Team)
Remake batch 22: rewritten from scratch under the authoring cheatsheet with datasheet constraints; scope boundaries restated against the remade neighbors

1 Scope

NOTE This standard covers the furnishing and field installation of interior finish carpentry built from stock material: standing and running trim from stock lumber and stock catalog moldings, jamb extensions and casing at door and window openings, stock closet shelving and rod, stock wood stair parts, and the field installation of items furnished by others where that installation is finish carpentry. (1.1)
NOTE Finish carpentry is the woodwork that is bought from a lumber yard or a molding catalog and made to fit in the room: the base where the wall meets the floor, the casing around a door, the crown at the ceiling, the shelf and rod in a closet. It is judged at arm's length on the fit of its joints, so a gap that would be invisible in framing is a defect here. (1.2)
NOTE Three standards divide interior woodwork, and the test that routes an item between them is how the item is made, not what it is called: (1.3)
  • Stock profile, field-cut and field-assembled from catalog moldings and lumber, with no shop drawing: finish carpentry, under this standard
  • Custom profile milled to a project drawing, or trim and paneling fabricated in a shop to shop drawings at an architectural woodwork grade: Architectural Wood Trim And PanelingArchitectural Wood Trim and PanelingResolves to the current adopted revision.sync/architectural-wood-trim-and-paneling
  • Cabinets, counters, and built-ins fabricated in a shop as boxes: Wood And Laminate CaseworkWood and Laminate CaseworkResolves to the current adopted revision.sync/wood-and-laminate-casework
  • Several of those types bought together under one millwork contract: Interior Architectural WoodworkInterior Architectural WoodworkResolves to the current adopted revision.sync/interior-architectural-woodwork, which coordinates the package and hands each stock item back to this standard
NOTE A base molding run against a wall is finish carpentry whether the room is a corridor or a boardroom; the same base becomes architectural woodwork the moment its profile is drawn for the project and run by a millwork shop. The grade language follows the route: architectural woodwork carries an AWI, WI, or AWMAC product grade, and stock trim carries a species, a lumber grade under the hardwood or softwood grading rules, a molding grade, a moisture content, and a profile number. (1.4)
NOTE The following are outside this standard: (1.5)
  • Wood door leaves, which are governed by Wood DoorsWood DoorsResolves to the current adopted revision.sync/wood-doors, and wood door frames and jambs, which are furnished by the trade that supplies the door and are not covered here; this standard furnishes the jamb extensions and the casing that trim the opening
  • Structural framing, including the stringers and carriages a stair is built on (Wood FramingWood Light FramingResolves to the current adopted revision.sync/wood-framing)
  • Non-structural blocking, backing, grounds, and furring, which are installed before the wall is closed (Rough CarpentryRough CarpentryResolves to the current adopted revision.sync/rough-carpentry), and the in-wall blocking that a steel-stud partition carries (Gypsum Board AssembliesGypsum Board AssembliesResolves to the current adopted revision.sync/gypsum-board-assemblies)
  • Field painting, staining, and clear finishing of the installed trim, and the filling of fastener holes in trim that receives an opaque finish (Interior PaintingInterior PaintingResolves to the current adopted revision.sync/interior-painting)
  • Wood finish flooring and its expansion base at the wall (Wood FlooringWood FlooringResolves to the current adopted revision.sync/wood-flooring), and resilient wall base (Resilient FlooringResilient FlooringResolves to the current adopted revision.sync/resilient-flooring)
  • Metal stairs, handrails, and guards (Metal Stairs And RailingsMetal Stairs and RailingsResolves to the current adopted revision.sync/metal-stairs-and-railings)
  • Exterior trim, siding, soffits, and any woodwork exposed to the weather
1.6 The extent, location, and profile designation of each trim element shall be as indicated on the trim schedule, interior elevations, and interior details.
1.7 The location, length, and depth of closet shelving and rod shall be as indicated on the floor plans and interior elevations.
1.8 The Contractor shall coordinate this work with Rough CarpentryRough CarpentryResolves to the current adopted revision.sync/rough-carpentry and Gypsum Board AssembliesGypsum Board AssembliesResolves to the current adopted revision.sync/gypsum-board-assemblies for the blocking and backing this trim is fastened to.
1.9 The Contractor shall coordinate this work with Wood DoorsWood DoorsResolves to the current adopted revision.sync/wood-doors and Doors Frames And HardwareDoors, Frames, and HardwareResolves to the current adopted revision.sync/doors-frames-and-hardware at every opening that receives casing or a jamb extension.
1.10 The Contractor shall coordinate this work with Interior PaintingInterior PaintingResolves to the current adopted revision.sync/interior-painting for the sequence of priming, filling, caulking, and finishing against the setting of trim.
1.11 The Contractor shall coordinate this work with Wood FlooringWood FlooringResolves to the current adopted revision.sync/wood-flooring and Resilient FlooringResilient FlooringResolves to the current adopted revision.sync/resilient-flooring at the base line, so that the base and shoe cover the flooring expansion gap without restraining the floor.

2 Referenced Standards

2.1 Materials and installation shall comply with the latest adopted edition of each of the following unless a specific edition is cited.
2.2 Where referenced standards conflict, the more stringent requirement shall govern unless the Engineer of Record directs otherwise in writing.
Standard Title
ANSI/AWI 0620 Finish Carpentry/Installation
NHLA Rules Rules for the Measurement and Inspection of Hardwood and Cypress
WWPA Western Lumber Grading Rules
PS 20 American Softwood Lumber Standard
WMMPA WM Series Wood Moulding Profiles and Quality Grades (Wood Moulding and Millwork Producers Association)
ANSI A208.2 Medium Density Fiberboard (MDF) for Interior Applications
ASTM D4444 Laboratory Standardization and Calibration of Hand-Held Moisture Meters
ASTM E84 Surface Burning Characteristics of Building Materials
UL 723 Test for Surface Burning Characteristics of Building Materials
40 CFR Part 770 Formaldehyde Standards for Composite Wood Products (TSCA Title VI)
CARB ATCM 93120 Airborne Toxic Control Measure to Reduce Formaldehyde Emissions from Composite Wood Products
IBC International Building Code (Chapter 8, Interior Finishes; Chapter 10, Means of Egress; Chapter 16, Structural Design)

3 Submittals

3.1 Action Submittals

3.1.1 The Contractor shall submit the following for the Engineer of Record's review, and shall not order material for an item until that item's submittals have been reviewed and returned:
  • Product Data: For each trim, shelving, and stair element: the species or material, the lumber grade and molding grade, the profile designation and a dimensioned profile section from the manufacturer's catalog, the stock lengths, the moisture content at shipment, the finish type, and the delivery state.
  • Samples: A 12 in. length of each profile in the specified material and delivery state, and for transparent-finished trim a sample of each species showing the grade and the color range the supplier will furnish.
  • Fastener and Adhesive Schedule: The fastener type, size, and finish and the adhesive type for each trim material and each substrate it is fastened to.
  • Installation Instructions: The manufacturer's published installation instructions for cellular PVC trim, foam plastic trim, and any item with a proprietary clip or fastening system.
Action Submittals Requiredcheckbox
☑ Product data with species, grade, profile section, moisture content, finish type, and delivery state
☑ Profile and species samples
☑ Fastener and adhesive schedule
☐ Manufacturer's installation instructions for non-wood and clip-fastened trim
NOTE Shop drawings are not a submittal under this standard. A profile that needs a shop drawing to be understood is not a stock profile, and the item belongs under Architectural Wood Trim And PanelingArchitectural Wood Trim and PanelingResolves to the current adopted revision.sync/architectural-wood-trim-and-paneling. The product data substitute for the shop drawing is the catalog section, which fixes the profile by number so that the installed piece can be checked against what was reviewed. (3.1.1.1)

3.2 Informational Submittals

3.2.1 The Contractor shall submit the following for record before the corresponding work begins:
  • Moisture and Conditioning Record: The interior temperature and relative humidity readings and the wood moisture content readings taken at delivery, at the end of acclimatization, and at the completion of installation.
  • Fire-Test Documentation: The ASTM E84 or UL 723 report for each trim material at a location where the trim is regulated as an interior finish, and the evaluation report for foam plastic trim.
  • Formaldehyde Compliance Documentation: Certification or labeling establishing compliance of every composite-wood component with 40 CFR Part 770 and CARB ATCM 93120 at the level identified in the datasheet.
Informational Submittals Requiredcheckbox
☑ Moisture content and interior conditioning record
☐ Fire-test reports and foam plastic evaluation report
☑ Composite-wood formaldehyde compliance documentation

3.3 Closeout Submittals

3.3.1 The Contractor shall submit the following at Substantial Completion:
  • Attic Stock Inventory: A written inventory of the attic stock delivered, identifying each item by profile designation, species or material, delivery state, and length, and its storage location.
  • Filler and Touch-Up Record: The color-matched filler and touch-up material used on transparent-finished trim, identified by product and color.
  • Warranty Documentation: The executed installation warranty required by this standard.
Closeout Submittals Requiredcheckbox
☑ Attic stock inventory by profile, material, delivery state, and length
☐ Color-matched filler and touch-up record
☑ Executed installation warranty

4 Quality Assurance

4.1 Installer Qualifications

4.1.1 The installer shall be a firm regularly engaged in finish carpentry of the type and grade specified, and shall submit a list of at least three completed projects of comparable scope.
NOTE Two manufacturers' versions of the same nominal profile differ by a few thousandths of an inch in width and in the radius of the curves, and the difference shows at every joint between them. One catalog per profile per area is what keeps a run continuous. (4.1.2.1)

4.2 Installation Grade

4.2.1 The installation grade under ANSI/AWI 0620 shall be as indicated in the datasheet.
Installation Graderadio
○ Economy
● Custom
○ Premium
4.2.2 Installed work shall meet the tolerances of ANSI/AWI 0620 for the specified installation grade for plumb, level, flatness of plane, joint tightness, reveal uniformity, and fastener concealment.
4.2.3 Where the Contractor and the Engineer of Record disagree whether an observed condition is within the specified grade tolerance, the Engineer of Record shall make the initial determination by measurement against the ANSI/AWI 0620 requirement for the grade.
NOTE The installation grade is the one AWI grade that applies to stock trim. It governs the erected result rather than the material: how tight a joint closes, how uniform a reveal runs, how far a run can be out of plumb over its length, and whether a fastener can show. Under the AWI standards Custom Grade applies where the Contract Documents name no grade, so a project that is silent on grade has already selected Custom. Premium tightens every tolerance at a labor cost that is visible where trim is viewed closely in good light; Economy loosens them where the trim is in a back-of-house room or is painted and seen from a distance. (4.2.3.1)

4.3 Mockup

4.3.1 Whether a trim mockup is required shall be as indicated in the datasheet.
Trim Mockup Requiredradio
○ Required
○ Not required
4.3.2 Where a mockup is required, it shall be a short run of each profile carrying an inside corner, an outside corner, a running joint, and a casing head joint, built with the specified material and delivery state, at a location the Engineer of Record designates.
4.3.3 The Contractor shall obtain the Engineer of Record's written acceptance of a required mockup before setting the corresponding trim elsewhere.
4.3.4 An accepted mockup shall establish the standard of quality for the corresponding work and may remain in the finished work if it is undamaged and in a location shown to receive that work.
NOTE A mockup settles the coped and mitered joints, the reveal, and the delivery state before the first full room is trimmed, when a rejected corner costs one piece. It is worth its cost on transparent-finished work and on Premium Grade work, and buys little on painted base and casing at Custom Grade. (4.3.4.1)

5 Interior Conditions and Wood Moisture Content

5.1 Building Readiness Before Delivery

5.1.1 Trim, shelving, and stair parts shall not be delivered to the building until the building is enclosed and weather-tight.
5.1.2 Trim, shelving, and stair parts shall not be delivered to the building until concrete, masonry, plaster, and gypsum board finishing operations in the receiving space are complete and the affected construction is dry.
5.1.3 Trim, shelving, and stair parts shall not be delivered to the building until interior temperature and relative humidity are being held within the ranges indicated in the datasheet.
5.1.4 The source of interior conditioning before and during delivery, acclimatization, and installation shall be as indicated in the datasheet.
Interior Conditioning Source Before and During Installationradio
○ Permanent HVAC system in operation
○ Temporary conditioning maintaining the specified humidity range
○ Either, at the Contractor's option, provided the specified range is maintained and recorded
NOTE Wood is hygroscopic: it exchanges moisture with the surrounding air until it reaches equilibrium and changes dimension across the grain as it does. Trim set before the building's service condition is established shrinks and opens its joints, or swells and buckles, once that condition arrives. A slab that is still drying and a construction heater that burns fuel inside the space both load the air with moisture, and a count of calendar days does nothing about either. (5.1.4.1)
NOTE A permanent HVAC system holds the actual service condition the trim will live in; temporary conditioning can hold the same numbers but is removed at some point before occupancy, so the recorded humidity log is the only evidence that the range was continuous. (5.1.4.2)

5.2 Service Relative Humidity Range

5.2.1 The minimum and maximum interior relative humidity to be maintained at delivery, during installation, and in service shall be as indicated in the datasheet.
Lowest Interior Relative Humidity in Servicerange
Not less than
% RH
1550
Highest Interior Relative Humidity in Servicerange
Not more than
% RH
4575
NOTE The humidity range that suits wood trim is regional. Across most of the United States and Canada an interior range near 25% to 55% RH corresponds to the moisture content stock moldings are kiln-dried to; the damp southern coastal region runs higher, near 43% to 70% RH, and the dry southwestern United States and the Canadian prairie provinces run lower, near 20% to 50% RH. A range written for another region produces trim that opens its joints while meeting every material requirement. (5.2.1.1)

5.3 Wood Moisture Content at Delivery

5.3.1 The minimum and maximum moisture content of solid and finger-jointed wood trim, shelving, and stair parts at delivery and at installation shall be as indicated in the datasheet.
Lowest Wood Moisture Content at Deliveryrange
Not less than
%
310
Highest Wood Moisture Content at Deliveryrange
Not more than
%
615
5.3.2 The Contractor shall measure and record the moisture content of a representative sample of each species and product on arrival at the site with a hand-held meter calibrated under ASTM D4444 for the species, and shall report a reading outside the specified range to the Engineer of Record before the material is installed.
5.3.3 Where the Contractor and the Engineer of Record disagree whether a reading is representative, the Engineer of Record shall make the initial determination and may direct additional readings at the Contractor's cost.
NOTE Moisture content and the service humidity range are two views of one equilibrium. Across most of the United States and Canada a 25% to 55% RH service range corresponds to roughly 5% to 10% moisture content; the damp southern coastal region corresponds to roughly 8% to 13%, and the dry southwest and prairie provinces to roughly 4% to 9%. Stock moldings leave the mill near the middle of the general range, so the delivered reading is normally inside it unless the material was stored wet on the way. (5.3.3.1)
NOTE Framing lumber is dried to a far higher moisture content than finish material and is not interchangeable with it, even for a concealed cleat or a nailer inside a closet. A meter reading on a resin-dense species, on MDF, or on cellular PVC is not a wood moisture reading, and only solid and finger-jointed wood is measured under this article. (5.3.3.2)

5.4 Acclimatization Before Installation

5.4.1 The minimum period material is held in the conditioned space before installation begins shall be as indicated in the datasheet.
Acclimatization Period in the Conditioned Spacerange
Not less than
hours
24487296120168
5.4.2 The Contractor shall stack acclimatizing material flat, fully supported, and stickered so air circulates around every piece.
5.4.3 The Contractor shall verify by moisture reading that wood material is within the specified moisture content range before installation begins, regardless of the elapsed acclimatization period.
NOTE The elapsed period is a scheduling commitment; the moisture reading is the acceptance criterion. Material that arrives already at equilibrium needs no waiting period, and material that arrives far off equilibrium will not reach it in a fixed number of hours, which is why a period of zero is a legitimate selection when readings govern. Medium density fiberboard and cellular PVC carry no wood moisture reading and are acclimatized for the period alone, PVC so that it is cut at the temperature it will serve at. (5.4.3.1)

6 Work Elements

6.1 The finish carpentry elements included in the work shall be as indicated in the datasheet, in the extent the drawings show.
Finish Carpentry Elements Includedcheckbox
☑ Base and shoe
☑ Door casing and jamb extensions
☐ Window casing, stool, and apron
☐ Chair rail
☐ Crown and bed mold
☐ Picture mold
☐ Closet shelving and rod
☐ Stock wood stair parts
☐ Field installation of items furnished by others
6.2 Where an element is included, every occurrence of it that the drawings show shall be furnished and installed under this standard unless the drawings assign a specific occurrence to another standard.
NOTE Base and door casing appear on nearly every project that carries this standard, and the rest follow the design: a chair rail where walls are protected or divided, a crown where the room is finished to a ceiling line, a picture mold where art is hung, a stool and apron at a wood-trimmed window. The checklist is what tells a bidder which items are priced here rather than under the millwork or casework package. (6.2.1)

7 Trim Materials

7.1 Finish Type

7.1.1 The finish type of each trim element shall be as indicated in the datasheet.
Trim Finish Typeradio
○ Transparent
○ Opaque
Per drawings — the finish schedule (deferred by default)
7.1.2 The finish type governs which material article below applies to the element, which molding grade the element is furnished at, and which delivery state applies.
NOTE A transparent finish shows the wood, so the material is selected for species, color, and grain, and every joint and filled hole shows. An opaque finish hides the substrate, so the material is selected for how it machines and holds a film, and finger joints, composite board, and polymer profiles all become candidates. Painted trim against stained doors is a common schedule, which is why the finish type is scheduled per element rather than per project. (7.1.2.1)

7.2 Material for Opaque-Finished Trim

7.2.1 The material for trim that receives an opaque finish shall be as indicated in the datasheet.
Opaque-Finished Trim Materialselect
Finger-jointed pine
Finger-jointed poplar
Clear pine
Poplar
Soft maple
Medium density fiberboard
Moisture-resistant medium density fiberboard
Cellular PVC
Foam plastic molding
7.2.2 Medium density fiberboard trim shall be a molding-grade board conforming to ANSI A208.2, with a machined profile free of fuzz and torn fiber.
7.2.3 Cellular PVC trim shall be an interior-rated product with a current evaluation report from an accredited evaluation service covering its surface burning characteristics and its use as interior trim.
7.2.4 Foam plastic molding shall comply with the density, thickness, width, area, and flame spread limits that Adopted Building CodeAdopted Building CodeParameterEach project supplies its own value.adopted-building-code places on foam plastic interior trim, and shall bear the manufacturer's label identifying the product and its listed flame spread index.
NOTE Finger-jointed pine is the least expensive solid-wood paint-grade trim and is stocked primed in long lengths; the joints are invisible under paint and telegraph under anything else. Poplar and soft maple are close-grained hardwoods that take a crisp profile and a smooth enamel and hold a fastener well, at a higher cost than pine. Clear pine is selected where the design wants a softwood profile without joints, at a cost above finger-jointed stock. Medium density fiberboard machines a routed profile with no grain raise and no knots, is the flattest and straightest of the options, and is stocked primed; it swells irreversibly where liquid water reaches it, holds a fastener poorly in its edge, and is the heaviest material per foot. The moisture-resistant grade resists incidental wetting and humidity swings but is not a wet-location product. Cellular PVC is unaffected by water and is selected for restrooms, locker rooms, and wet-cleaned floors; it moves with temperature rather than humidity, cannot be stained, and needs its own fasteners and adhesive. Foam plastic molding is light, is stocked in large crown profiles that would be costly in wood, and is limited by the building code in density, size, area, and flame spread. (7.2.4.1)

7.3 Species for Transparent-Finished Trim

7.3.1 The species for trim that receives a transparent finish shall be as indicated in the datasheet.
Transparent-Finished Trim Speciesselect
Red oak
White oak
Hard maple
Soft maple
Poplar
Cherry
Black walnut
Ash
Hickory
Alder
Birch
Clear pine
Douglas fir
Western red cedar
Per drawings — the finish schedule (deferred by default)
NOTE Species sets color, hardness, grain figure, and cost, and it also sets how a stain reads: the same stain on red oak, hard maple, and cherry produces three different colors, which is why the finish sample under Interior PaintingInterior PaintingResolves to the current adopted revision.sync/interior-painting is approved on the actual species. The oaks, ash, and hickory are open-grained and show pore and figure; maple, cherry, birch, alder, and poplar are close-grained and take a stain evenly, and poplar's green and gray streaks limit it to dark stains. Pine, fir, and cedar are softwoods that dent under a fingernail and are selected where the design wants their figure and color. Stock moldings are run in every one of these species but not in every profile; a profile wanted in an uncommon species is confirmed as a catalog item before it is scheduled. (7.3.2.1)

7.4 Hardwood Lumber Grade

7.4.1 Hardwood lumber and hardwood stair parts furnished under this standard shall be graded under the NHLA Rules at the grade indicated in the datasheet.
Hardwood Lumber Gradeselect
FAS
FAS One Face
Selects
No. 1 Common
NOTE The NHLA grades are based on the yield of clear cuttings from a board. FAS yields the largest clear cuttings from both faces and is the grade long clear trim and stair parts are cut from; FAS One Face holds the FAS yield on the face that shows and admits the No. 1 Common yield on the back, which suits trim seen from one side; Selects is a narrower and shorter FAS One Face; No. 1 Common yields shorter clear cuttings and is selected where the pieces are short, where character is wanted, or where cost governs. A long base run cut from No. 1 Common is a run with joints in it. (7.4.1.1)

7.5 Softwood Lumber Grade

7.5.1 Softwood lumber furnished under this standard shall be graded under PS 20 and the WWPA Western Lumber Grading Rules or the equivalent rules of the regional grading agency, at the grade indicated in the datasheet.
Softwood Lumber Gradeselect
B and Better Select
C Select
D Select
Superior Finish
Prime Finish
NOTE The Select grades are the appearance grades of the western and northeastern rules: B and Better Select is practically clear, C Select admits a few small characteristics on the face, and D Select admits more and is normally confined to paint. Superior and Prime are the Finish grades the same rules apply to Douglas fir, hem-fir, and the pines in some regions, Superior corresponding roughly to C Select and Prime to D Select. The grade names and their limits are set by the rule-writing agency, and a bidder reads them from the grade stamp or the invoice. (7.5.1.1)

7.6 Molding Grade

7.6.1 Stock wood moldings shall be furnished at the WMMPA grade indicated in the datasheet.
Stock Wood Molding Gradeselect
N-Grade
P-Grade
Derived — the trim finish type: N-Grade for a transparent finish, P-Grade for an opaque finish (by default)
NOTE The molding grades are set by the molding industry rather than the lumber graders and describe the run profile rather than the board it came from. N-Grade is cut for a natural finish, with no finger joints and a face free of the characteristics a stain would show; P-Grade is cut for paint and admits finger joints and the small, sound characteristics a primer and two coats cover. The grade follows the finish type, so it is derived rather than selected, and the engineer overrides it only to require N-Grade under a paint where no joint is to telegraph. (7.6.1.1)

7.7 Delivery State of Opaque-Finished Trim

7.7.1 The delivery state of trim that receives an opaque finish shall be as indicated in the datasheet.
Opaque-Finished Trim Delivery Stateradio
● Factory-primed
○ Unprimed
○ Factory-finished
7.7.2 Factory primer shall be compatible with the topcoat system under Interior PaintingInterior PaintingResolves to the current adopted revision.sync/interior-painting and shall be identified in the product data.
7.7.3 Where unprimed trim is selected, the Contractor shall back-prime it and prime its cut ends before installation under the primer system of Interior PaintingInterior PaintingResolves to the current adopted revision.sync/interior-painting.
NOTE Finger-jointed and fiberboard moldings are stocked primed, so the primed state is what a paint-grade order arrives in unless something else is asked for. Unprimed stock is selected where the finish system wants its own primer or where the primer must be tinted; it adds a field priming operation and leaves the back and the cut ends to be primed on site. A factory-finished molding arrives with its topcoat on, saves the painting trade a pass, and has to be set with the fill, caulk, and paint operations already ruled out, so every fastener hole and every wall joint on it is touched up rather than painted over. (7.7.3.1)

7.8 Delivery State of Transparent-Finished Trim

7.8.1 The delivery state of trim that receives a transparent finish shall be as indicated in the datasheet.
Transparent-Finished Trim Delivery Stateradio
● Unfinished
○ Factory-sealed
○ Factory-finished
7.8.2 Where factory-finished trim is selected, the Contractor shall seal every field cut with the manufacturer's matching material and shall fill fastener holes with a filler matched to the finished color before the trim is accepted.
NOTE Stain-grade stock moldings are sold unfinished and are stained and clear-coated in place under Interior PaintingInterior PaintingResolves to the current adopted revision.sync/interior-painting, which is how the trim is matched to the doors and the floor. A factory seal protects the wood through delivery and leaves the color to the field; a factory finish fixes the color before the adjacent woodwork is finished and leaves field repair of a damaged face to a touch-up kit. (7.8.2.1)

7.9 Trim at Wet and High-Humidity Locations

7.9.1 The locations at which trim is exposed to wetting, to wet cleaning of the floor, or to sustained high humidity shall be as indicated on the room finish schedule.
7.9.2 The trim material at those locations shall be as indicated in the datasheet.
Trim Material at Wet and High-Humidity Locationsselect
Cellular PVC
Moisture-resistant medium density fiberboard
Solid wood, opaque-finished, back-primed and end-sealed
Same material as the dry locations
7.9.3 Standard medium density fiberboard shall not be used at a location designated wet unless the datasheet selects it as the same material as the dry locations.
NOTE The base at a restroom, a janitor closet, or a locker room floor is mopped daily and stands in water when a fixture overflows. Cellular PVC takes that service without change; moisture-resistant fiberboard takes the humidity and the incidental splash but not standing water; back-primed and end-sealed solid wood takes it for the life of its paint film. Keeping one material throughout is a legitimate policy where the Owner accepts replacing the base at the wet rooms, and where the wet rooms carry a resilient or tile base instead of wood this field does not apply. (7.9.3.1)

7.10 Composite-Wood Formaldehyde Emissions

7.10.1 Every composite-wood component furnished under this standard, including medium density fiberboard trim, particleboard and fiberboard shelving, and veneered plywood shelving, shall comply with 40 CFR Part 770 and CARB ATCM 93120 and shall be labeled or certified accordingly.
7.10.2 The compliance level required shall be as indicated in the datasheet.
Composite-Wood Formaldehyde Compliance Levelradio
● TSCA Title VI and CARB Phase 2 certified
○ Ultra-low-emitting formaldehyde (ULEF) exempt panels
○ No-added-formaldehyde (NAF) exempt panels
NOTE Compliance with 40 CFR Part 770 is a condition of lawful sale in the United States and is not a project option; the datasheet selection determines only whether the project requires the further ULEF or NAF exemption levels, which a green-building program or an Owner's indoor air policy can call for. The exemptions are granted to the panel producer, so a ULEF or NAF molding is a supply question confirmed in the product data rather than a specification the installer can meet by choice. (7.10.2.1)

8 Interior Finish Fire Classification

NOTE Trim is regulated under Chapter 8 of Adopted Building CodeAdopted Building CodeParameterEach project supplies its own value.adopted-building-code as interior trim where it covers not more than the code's share of the wall or ceiling area of a room, and as interior wall or ceiling finish where it covers more. (8.1)
8.2 The flame spread class required of trim shall be as indicated in the datasheet.
Required Flame Spread Class of Trimradio
○ Class A
○ Class B
● Class C
8.3 Where trim exceeds the interior trim area limit of Adopted Building CodeAdopted Building CodeParameterEach project supplies its own value.adopted-building-code in a room, the trim in that room shall meet the interior wall and ceiling finish class the code requires for the occupancy and location, and that class shall be as indicated on the code analysis and life safety plans.
8.4 The classification shall be established by ASTM E84 or UL 723 testing of the trim material in the form it is installed, including any factory finish.
NOTE Class A is a flame spread index of 0 to 25, Class B is 26 to 75, and Class C is 76 to 200, each with a smoke-developed index limit of 450. The IBC treats base, casing, chair rail, and similar trim within its area limit as interior trim and requires Class C of it in every occupancy, which untreated wood and primed fiberboard meet, so Class C is the class nearly every stock trim order carries. A room whose wall is largely covered by applied trim, or a design that stacks moldings into a cornice covering a large share of the ceiling, crosses into interior finish and takes the class of the occupancy, which in a corridor, an exit enclosure, or an assembly or institutional space is Class A or B. Foam plastic trim carries its own flame spread limit under the code, set lower than Class C. (8.4.1)
NOTE A field-applied finish does not change the classification of the trim unless the finish is a listed fire-retardant coating applied as its listing requires, and a fire-retardant coating is not a route this standard offers. Trim that cannot meet the required class untreated is pressure-treated fire-retardant wood, which is custom-run and belongs under Architectural Wood Trim And PanelingArchitectural Wood Trim and PanelingResolves to the current adopted revision.sync/architectural-wood-trim-and-paneling. (8.4.2)

9 Installation

9.1 Blocking and Backing

9.1.1 The trade that furnishes and installs the concealed blocking and backing this trim is fastened to shall be as indicated in the datasheet.
Concealed Blocking and Backing Furnished Underradio
● The wall and ceiling framing trades
○ The Contractor performing the work of this standard
9.1.2 Before installation begins the Contractor shall verify that blocking or framing is present behind every chair rail, every base taller than 5-1/2 in., every crown that is fastened to the wall rather than to the ceiling framing, every closet shelf cleat and rod support, every handrail bracket, and every item furnished by others that this standard installs.
9.1.3 The Contractor shall notify the Engineer of Record of missing or mislocated blocking before proceeding, and shall not fasten trim over a known deficiency.
9.1.4 Base, casing, and other trim within the reach of a framing member shall be fastened to the framing, and the gypsum board alone shall not carry a trim element that bears a load or is struck in service.
NOTE Blocking is installed by the framing trades under Rough CarpentryRough CarpentryResolves to the current adopted revision.sync/rough-carpentry and Gypsum Board AssembliesGypsum Board AssembliesResolves to the current adopted revision.sync/gypsum-board-assemblies before the wall is closed, which is why the trim layout has to be known before the board goes on. A chair rail hit by a chair back, a tall base kicked by a cart, and a closet rod loaded with coats all pull on their fasteners, and a fastener in gypsum board alone pulls out. Standard-height base and casing land on the bottom plate and the jamb studs and need no separate blocking, which is why the verification is tied to the items that do. (9.1.4.1)

9.2 Layout and Running Joints

9.2.1 The Contractor shall lay out each run to minimize the number of joints in it and to place the joints that stock lengths require away from the center of a wall and away from sightlines where the stock length allows.
9.2.2 Running joints in trim shall be scarf joints cut at not less than 45 degrees to the face, glued, and located over a framing member or blocking.
9.2.3 Unless the Contract Documents indicate otherwise, a square butt joint shall not be used as a running joint in exposed trim.
9.2.4 Long runs shall be measured and cut from a fixed reference so that cutting error does not accumulate along the run.
NOTE A scarf joint laps the two pieces so that shrinkage opens a feathered line rather than a square gap, and landing it on solid backing lets both pieces be fastened at the joint; a scarf floating over a stud cavity opens as the building cycles through its first season. The 45 degree angle is the shallowest that hides the joint under paint; stain-grade work is commonly scarfed shallower, which uses more length. (9.2.4.1)

9.3 Inside and Outside Corners

9.3.1 The inside-corner joint in profiled running trim shall be as indicated in the datasheet.
Inside-Corner Joint in Profiled Running Trimradio
● Coped
○ Mitered
○ Butted to a corner block
9.3.2 The outside-corner joint in profiled running trim shall be as indicated in the datasheet.
Outside-Corner Joint in Profiled Running Trimradio
● Mitered
○ Butted to a corner block
9.3.3 Mitered outside corners shall be glued and shall be fastened through both faces of the corner so that the miter is held closed from both sides.
9.3.4 Where the material does not permit coping, as with a cellular PVC or foam plastic profile, the inside corner shall be mitered and bonded with the adhesive the manufacturer specifies for that material.
NOTE A coped inside corner cuts one member to the reverse profile of the other, so the joint closes on a profile line rather than on a glue line; it holds its appearance when the wall corner is out of square and when the members shrink, both of which open a mitered inside corner. A mitered outside corner is the only joint that carries the profile continuously around a projecting corner. Corner blocks and plinths remove the corner joint from the profile entirely by terminating both runs against a square block, which is a design decision about how the trim reads rather than a fallback for a difficult corner. (9.3.4.1)

9.4 Casing and Jamb Extensions at Openings

9.4.1 Casing at each door and window opening shall be set to a uniform reveal from the face of the jamb, and the reveal shall be as indicated in the datasheet.
Casing Reveal From the Jamb Facerange
in.
0.1250.18750.250.31250.375
9.4.2 The joint between the head casing and the leg casings shall be as indicated in the datasheet.
Casing Head Jointradio
● Mitered
○ Butted head casing
○ Rosette and plinth blocks
9.4.3 Mitered casing head joints shall be glued and shall be fastened across the miter so that the joint does not open as the casing shrinks.
9.4.4 Where the jamb furnished with the door or window does not reach the face of the finished wall, the Contractor shall furnish a jamb extension of the casing material, ripped to bring the jamb flush with the wall and fastened to the jamb so that the casing reveal is uniform on both sides of the opening.
9.4.5 Window stools shall be notched around the jambs and returned on the ends, and the apron shall be cut to the width of the casing and returned on its ends.
9.4.6 The Contractor shall coordinate the casing reveal with the hinge and strike locations under Door HardwareDoor HardwareResolves to the current adopted revision.sync/door-hardware or Doors Frames And HardwareDoors, Frames, and HardwareResolves to the current adopted revision.sync/doors-frames-and-hardware so that no hinge leaf or strike plate is covered.
NOTE A 1/4 in. reveal is what stock casing and stock jambs are made for and is the reveal nearly every opening is trimmed to; a narrower reveal is selected for a thin casing and a wider one for a heavy profile. A mitered head joint carries the profile continuously around the opening and is the joint stock casing is designed for; a butted head casing sets a thicker head over square-cut legs and suits a flat or beaded casing; rosette and plinth blocks terminate the legs and head against square blocks at the corners and the floor, which puts no miter on the opening and is selected for a traditional design or where the legs and head are different profiles. The jamb extension exists because wood door jambs are made for a 4-9/16 in. wall and the wall is often thicker. (9.4.6.1)

9.5 Fastening

9.5.1 The fastening method for trim shall be as indicated in the datasheet.
Trim Fastening Methodselect
Pneumatic finish nails, set and filled
Trim-head screws, countersunk and filled
Adhesive with pin nails
Concealed clips on a continuous carrier
9.5.2 Trim shall be fastened at each framing member it crosses and at a spacing along the run not greater than that indicated in the datasheet.
Fastener Spacing Along Running Trimrange
Not more than
in.
8121624
9.5.3 Fasteners shall be of a length that penetrates the framing or blocking by not less than 3/4 in. and shall be placed so that no fastener head lies within the profile's visible curves where the material allows.
9.5.4 Fasteners in cellular PVC trim shall be stainless steel or a corrosion-resistant coated fastener the trim manufacturer identifies for the product, and shall be driven at the spacing the manufacturer publishes.
9.5.5 Fasteners in trim fastened to preservative-treated or fire-retardant-treated blocking shall be hot-dip galvanized or stainless steel.
9.5.6 Fastener holes in trim that receives an opaque finish shall be filled under Interior PaintingInterior PaintingResolves to the current adopted revision.sync/interior-painting after the trim is primed.
9.5.7 Fastener holes in trim that receives a transparent finish shall be filled with a filler matched to the finished color after the first finish coat is applied, by the Contractor performing the work of this standard, coordinated with Interior PaintingInterior PaintingResolves to the current adopted revision.sync/interior-painting.
NOTE A set finish nail is the fastest method, holds a stock profile adequately, and leaves a hole that disappears under paint; it is what nearly every trim run is set with. A trim-head screw draws a bowed piece tight to an uneven wall and holds in dense hardwood or in a hollow substrate where a nail would not, at the cost of a larger hole. Adhesive with pin nails leaves almost no hole and is selected for transparent-finished work and for fiberboard whose edge will not hold a nail; the pins hold the piece until the adhesive cures. Concealed clips put no fastener in the face at all and are selected where a factory-finished molding is to show no filler. (9.5.7.1)
NOTE Treated lumber corrodes bright steel, and cellular PVC moves enough with temperature to work a bright nail loose; both call for their own fastener. A filled hole in a painted member disappears under the film; the same hole in a transparent-finished member remains a visible spot of a different color unless the filler is matched to the finished wood rather than the raw wood, which is why the filling waits for the first coat. (9.5.7.2)

9.6 Scribing, Fitting, and Wall Joints

9.6.1 Trim meeting walls, floors, ceilings, and adjacent finishes shall be scribed to the contour of the adjacent surface where the installation grade requires a closed joint, so that the joint closes tight and reads uniform.
9.6.2 Transparent-finished trim shall be scribed to the adjoining surface and shall not be caulked to it.
9.6.3 The joint between opaque-finished trim and the adjoining wall or ceiling surface shall be closed with a paintable acrylic latex sealant before the finish coats are applied, and the trade that applies the sealant shall be as indicated in the datasheet.
Caulking of Trim-to-Wall Joints Performed Underradio
○ The painting trade, under interior painting
○ The Contractor performing the work of this standard
9.6.4 Material shall be cut and back-cut so that face joints close before fastening, and a joint shall not be drawn closed by the fastener.
9.6.5 Trim shall be fitted to the floor finish as installed: base shall be set to clear the finish flooring by the gap the flooring standard requires for expansion, and shoe shall be fastened to the base, not to the floor.
NOTE Building surfaces are rarely flat, plumb, or square, so a piece set against an untouched wall leaves a tapered gap that widens along its length. Under paint the gap is caulked and painted with the wall, and the trade that caulks is a coordination decision between the carpenter who knows the joint and the painter who is already masking it; under a transparent finish a caulk line is a visible bead of another material, so the piece is scribed instead. The base is set above the floor rather than on it because a wood or resilient floor expands under it, and a shoe nailed to the floor pins the floor at the wall. (9.6.5.1)

9.7 Cellular PVC and Foam Plastic Trim

9.7.1 Cellular PVC trim shall be installed with the expansion gaps, the adhesive at joints, and the fastener spacing the manufacturer publishes for the length and the service temperature range.
9.7.2 Joints in cellular PVC trim shall be bonded with the PVC cement the manufacturer identifies, so that the run moves as one piece rather than at each joint.
9.7.3 Foam plastic molding shall be installed with the adhesive and the fasteners the manufacturer identifies, and shall not be installed where its listed flame spread index or its area limit under Adopted Building CodeAdopted Building CodeParameterEach project supplies its own value.adopted-building-code would be exceeded.
NOTE Cellular PVC does not move with humidity but does move with temperature, by roughly 1/4 in. over a 16 ft length across a 50°F swing, which is more than wood moves across a season. Gluing the running joints turns a long run into one piece whose total movement is taken at its ends, behind a corner or a casing, rather than as an opening gap at every joint. Foam plastic is set with adhesive because it will not hold a nail; its code limits are the reason the material is confirmed against the room before it is ordered. (9.7.3.1)

9.8 Closet Shelving and Rod

9.8.1 The material of stock closet shelving shall be as indicated in the datasheet.
Closet Shelving Materialselect
Melamine-faced particleboard
Solid pine
Medium density fiberboard, primed
Veneered plywood with a hardwood front edge
9.8.2 The closet rod shall be as indicated in the datasheet.
Closet Rodselect
Hardwood dowel
Chrome-plated steel tube
Oval steel rod with end flanges
9.8.3 Shelves shall be not less than 3/4 in. thick, supported on cleats at the back and both ends, and fastened to the cleats.
9.8.4 Shelves and rods shall have an intermediate support at a spacing not greater than that indicated in the datasheet.
Closet Shelf and Rod Support Spacingrange
Not more than
in.
24323648
9.8.5 Rod supports shall be fastened to blocking or framing, and the rod shall be set at the height indicated on the interior elevations.
9.8.6 Melamine-faced and veneered shelving shall be edged on the front edge, and every exposed edge of a composite shelf shall be banded or finished so that no core is left open.
NOTE A melamine-faced particleboard shelf needs no finish and wipes clean, is the least expensive, and sags over a long span under a loaded rod. Solid pine and primed fiberboard are painted with the trim and read as part of it; pine holds a screw and a cleat nail well, fiberboard is flatter and heavier. Veneered plywood with a hardwood edge is selected for a transparent finish or for a long span. A wood dowel matches a stained closet and deflects under a full rod of coats beyond about 36 in.; a steel tube or an oval rod spans farther and is selected where the closet is wide. (9.8.6.1)

9.9 Stock Wood Stair Parts

9.9.1 Stock wood stair treads, risers, skirtboards, handrails, newels, and balusters, where included in the work, shall be furnished in the species and grade selected for transparent-finished trim or the material selected for opaque-finished trim, as the finish schedule indicates for the stair.
9.9.2 Treads and risers shall be glued and fastened to the stringers or carriages furnished under Wood FramingWood Light FramingResolves to the current adopted revision.sync/wood-framing, and a tread shall not be fastened to a riser alone.
9.9.3 Handrails and guards assembled from stock parts shall resist the handrail and guard loads of Adopted Building CodeAdopted Building CodeParameterEach project supplies its own value.adopted-building-code, and the handrail profile and its height shall meet the graspability and height provisions of that code.
9.9.4 Newels shall be anchored to the stair framing or the floor framing with the hardware the newel manufacturer identifies, and a newel shall not be anchored to the tread or the finish floor alone.
9.9.5 Handrail brackets shall be fastened to framing or blocking, at a spacing not greater than the bracket manufacturer's published spacing for the handrail loads.
NOTE Stock stair parts are catalog items in the same way stock moldings are, which is why they are finish carpentry rather than architectural woodwork; the structural stair they sit on is framing. The code loads on a handrail and a guard are structural requirements that the stock parts meet only when they are anchored into framing, and a loose newel is the most common failed inspection item on a wood stair. A stair in metal is governed by Metal Stairs And RailingsMetal Stairs and RailingsResolves to the current adopted revision.sync/metal-stairs-and-railings. (9.9.5.1)

9.10 Items Furnished by Others

9.10.1 Where the work includes the field installation of items furnished by the Owner or under another standard, the Contractor shall install them in accordance with the furnishing party's written instructions, into blocking or framing verified under this standard, and shall report a damaged or incomplete item to the Engineer of Record before it is installed.
9.10.2 The Contractor shall be responsible for an item from the time it is accepted for installation until Substantial Completion, and the furnishing party shall remain responsible for a defect in the item itself.
NOTE The handoff is written so that each party owns what it controls: the installer owns the anchorage and the fit, the furnishing party owns the product. An item accepted without inspection becomes the installer's problem when the defect is found after it is on the wall. (9.10.2.1)

10 Inspection of Completed Work

10.1 After installation the Contractor shall inspect the completed finish carpentry and shall correct or replace work that does not comply before requesting the Engineer of Record's review.
10.2 Running trim shall be checked for tight corner joints, closed running joints in the laid-out locations, uniform casing reveals, and conformance to the installation grade tolerances.
10.3 Exposed surfaces shall be checked for handling damage, torn profile edges, fastener heads not set, and filler that does not match.
10.4 Work that fails to meet the specified installation grade or that is damaged shall be corrected or replaced at the Contractor's cost, including the cost of refinishing a replaced piece to match its neighbors.

11 Delivery, Storage, and Handling

11.1 Delivery and On-Site Storage

11.1.1 Trim, shelving, and stair parts shall be delivered only after the building readiness conditions of this standard are satisfied.
11.1.2 Material shall be stored inside the conditioned space, flat, fully supported along its length, and protected from moisture, direct sunlight, and physical damage.
11.1.3 Material shall not be stored on a slab, against masonry or concrete, or in a space that is not within the specified humidity range.
11.1.4 Material that is bowed, cupped, twisted, split, or damaged on delivery shall be rejected and shall not be installed.
11.1.5 The Contractor shall bear the cost of storage, of conditioning during storage, and of replacing material damaged or distorted in storage.
NOTE A molding stored on a damp slab takes up water from the face in contact and cups toward the dry side, so it arrives at installation distorted even though its shipped moisture content was correct. Long stock lengths stored on two supports sag between them and take a set, which is why the support runs the full length. (11.1.5.1)

11.2 Protection During Construction

11.2.1 The Contractor shall protect installed trim, shelving, and stair parts from damage by other trades until Substantial Completion.
11.2.2 Protective covering shall not trap moisture against the wood, mark a finished surface, or leave adhesive residue.
11.2.3 Damage to installed work occurring after installation shall be repaired or the affected member replaced at the Contractor's cost, and a repair shall be indistinguishable from the surrounding work at normal viewing distance.

12 Warranty

12.1 The installation warranty period, measured from the date of Substantial Completion, shall be as indicated in the datasheet.
Installation Warranty Periodrange
Not less than
years
123510
12.2 The Contractor shall warrant the installation for the specified period against open joints, open miters, loose or detached trim, fastener pops, cupped or bowed members, and shelving or stair parts that loosen in service.
12.3 The Contractor shall correct a deficiency attributable to installation workmanship or to material delivered outside the specified moisture content range at no cost to the Owner, including the cost of refinishing the corrected piece to match and the cost of repairing collateral damage caused by the correction.
12.4 The warranty shall exclude movement caused by interior temperature or relative humidity outside the range specified in the datasheet, provided the material was delivered, acclimatized, and installed in compliance with this standard.
12.5 Work corrected under warranty shall carry a fresh warranty of the specified period running from the date of the correction, or the unexpired remainder of the original period, whichever ends later.

13 Attic Stock

13.1 The quantity of attic stock trim, expressed as a percentage of the installed length of each profile, shall be as indicated in the datasheet.
Attic Stock Trim Quantityrange
Not less than
%
010
13.2 Attic stock shall be from the same catalog, species or material, grade, and delivery state as the installed work, in full stock lengths, delivered wrapped and labeled with the profile designation and quantity, and stored where the Owner directs.
NOTE Stock profiles can be reordered by number for as long as the catalog carries them, which is why a project often carries no attic stock for trim at all. A profile that is run in an uncommon species, a factory-finished molding whose color will not be repeated, or a discontinued profile is the case for holding a few lengths, because the replacement would otherwise be a near match set beside the original. (13.2.1)

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