Wood Stair, Handrail, and Guard Systems

Proposed ANS AWI SMA 0643

THIS IS A DRAFT FOR REVIEW BY A CONSENSUS BODY AND NOT AN APPROVED STANDARD. NO Stairbuilders and Manufacturers Association PART OF THESE MATERIALS P.O Box 448 MAY BE DISTRIBUTED OR Dalton, OH 44618 USED FOR AWI STANDARDS Toll-Free: 877-500-5759 COMPLIANCE https://www.stairways.org Proposed ANS AWI SMA 0643 – October 2020 DRAFT FOR REVIEW ONLY - DO NOT DISTRIBUTE

Table of Contents 1.0 Purpose ...... 1 2.0 Scope ...... 1 2.1 Included ...... 1 2.2 Not Included ...... 1 3.0 Requirements ...... 2 3.1 General ...... 2 3.1.1 Measurements ...... 2 3.1.2 Special Requirements ...... 2 3.1.3 Environmental Conditions ...... 3 3.1.4 Manufacturer/Supplier Requirements for Installation ...... 3 3.1.5 Default Grade Requirements ...... 3 3.2 Material ...... 4 3.2.1 Stairs, Components ...... 5 3.2.2 Risers ...... 9 3.2.4 Platforms and Intermediate Landings ...... 10 3.2.5 Winders ...... 10 3.2.6 Guard and Handrail Components ...... 10 3.2.7 Handrails ...... 12 3.2.8 Rail and Fitting Connections ...... 13 3.2.9 Tolerances ...... 13 3.2.10 Fittings ...... 13 3.2.11 Guard In-Fill ...... 14 3.2.12 Well-Hole Trim ...... 16 3.3 Structural ...... 17 3.4 Aesthetic ...... 18 3.4.2 Transparent Finish ...... 19 3.4.3 Opaque Finish ...... 19 3.4.4 Stringers, Glued up ...... 19 3.4.5 Treads (Including Winders) ...... 19 3.4.6 Risers ...... 20 3.4.7 Guard and Handrail Components ...... 21 3.4.8 Fittings ...... 21 3.4.9 Guard, In-Fill ...... 22 3.4.10 Metal In-Fill/Guards ...... 23 3.4.11 Well-Hole Trim ...... 24

i Proposed ANS AWI SMA 0643 – October 2020 DRAFT FOR REVIEW ONLY - DO NOT DISTRIBUTE

3.4.12 Nosing, Well-Hole ...... 24 3.4.14 Staircase (Assembled Unit) ...... 25 3.5 Fabrication ...... 26 3.5.1 Stringers ...... 26 3.5.2 Risers ...... 27 3.5.3 Treads ...... 27 3.5.4 Stair Carriages (Concealed Stringers) ...... 27 3.6 Installation ...... 28 3.6.1 Field Assembled Stair Components ...... 29 3.6.2 Stairs, Shop Assembled ...... 31 3.6.3 Guard and Handrail Installation ...... 31 3.6.4 Fittings ...... 32 3.6.5 Guard, In-Fill ...... 33 4.0 Figures / Illustrations ...... 36 5.0 Supplemental Information ...... 39 5.1 Glossaries ...... 39 5.2 Design Professional Responsibilities ...... 39 5.3 Surface Categories ...... 39 5.3.1 Exposed ...... 39 5.3.2 Semi-Exposed ...... 39 5.3.3 Concealed ...... 39 5.4 SMA Supplemental Documents ...... 39 5.5 References ...... 39 5.6 Exceptions to Material Requirements ...... 40

ii Proposed ANS AWI SMA 0643 – October 2020 DRAFT FOR REVIEW ONLY - DO NOT DISTRIBUTE

1.0 Purpose a) Provide standards and tolerances for the quality fabrication and field installation of wood stair, handrail, and guard systems (henceforth referred to as “Product”). b) Establish minimum aesthetic and performance requirements intended to provide a well-defined degree of control over a project’s quality of materials, and workmanship, for the manufacture of wood stair, handrail, and guard systems. 2.0 Scope a) Provides aesthetic and performance standards for the manufacture and installation of interior wood stair, handrail, and guard systems for residential and commercial applications, including guard in-fill system components of metal, glass, and cable. 2.1 Included a) Product as specified under CSI MasterFormat Division: • 06 43 00 Wood Stairs and Railings 2.2 Not Included a) Substructures of materials other than wood b) Product as specified under CSI MasterFormat Division: • 05 00 00 Metals • 06 50 00 Structural Plastics • 09 65 00 Resilient Flooring c) Welding, polishing, grinding, machining, and finishing of metal components d) Structural components, grounds, in-wall blocking, backing, furring, support brackets, strapping, or other anchorage that becomes an integral part of the building’s walls, floor systems, or ceilings designed to support the required live loads are not furnished or installed under the scope of this standard’s requirements. e) Installation of Product items not specifically identified in itemized scope of work within the contract documents. f) Providing and installing electrical related items, light fixtures, network cables, grommets and wire management systems, computer equipment, or mechanical equipment. g) Correction of existing jobsite conditions that are required for the installation of the Product. h) All site-applied primers, stains, or other finish coatings for non-factory finished Product. i) Filling nail or screw holes in unfinished or primed Product. j) Caulking to fill voids between Product and pre-existing surfaces.

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3.0 Requirements 3.1 General a) The following requirements shall govern unless a project’s contract documents require otherwise. b) Should a conflict be discovered within this standard, the least restrictive requirement shall prevail. c) When metal components and/or fabrications are referenced within this standard, they shall comply with AMP 555 - Code of Standard Practice for the Architectural Metal Industry (latest edition) and AMP 500 - Metal Finishes Manual (latest edition). d) When applicable, manufacturer/supplier shall verify field measurements. 3.1.1 Measurements a) This standard is written with the metric system of measurement followed by the U.S. Customary System of measurement in brackets. b) The system of measurement used in the project’s original contract documents and architectural drawings shall dictate which system of measurement within these standards is used for verification of compliance. c) The U.S. Customary measurement is typically a “soft” conversion of the metric measurement. In order to make the metric number more conceptually coherent and consistent, most conversions for less than 152.4 mm [6”] in dimension are “soft” converted to the nearest 0.1 mm. For measurements above 152.4 mm [6”], the “soft” value is converted to the nearest 1 mm. d) “Inconspicuous,” when used in this standard, means not readily visible without careful inspection at a distance of: Premium Custom Economy 610 mm [24”] 1219 mm [48”] 1829 mm [72”]

e) Gaps and flushness between adjacent, exposed components shall be tested with a feeler gauge at points where components are required to contact as indicated within this standard. 3.1.2 Special Requirements a) If preservative treatment, chemical resistance, fire retardancy, or moisture resistance is required, fasteners shall be stainless steel, or a fastener recommended by the manufacturer/supplier. b) Where special physical and/or environmental construction requirements (e.g. seismic, flood, and/or high velocity wind) are required, such requirements and details shall be clearly stated in the contract documents.

Proposed ANS AWI SMA 0643 – October 2020 DRAFT FOR REVIEW ONLY - DO NOT DISTRIBUTE

c) Requirements for Product, such as preservative treated, moisture resistant, or fire-retardant materials, shall be specified by the design professional. 3.1.3 Environmental Conditions a) Requirements of this standard are contingent upon maintaining proper interior environmental controls prior to, during, and after installation. See the AWI 200 – Care & Storage Standard (latest edition). b) This standard does not establish grade requirements for joint flushness and gap tolerances for Product installed in a non-climate-controlled environment. c) Prior to installation, the flushness and gap tolerances of Products intended for non-climate-controlled environments shall meet the requirements herein. 3.1.4 Manufacturer/Supplier Requirements for Installation a) Manufacturer/supplier shall provide Product to comply with the contract documents. b) Manufacturer/supplier shall provide drawings indicating location of anchorage/blocking. See AWI 100 - Submittals Standard (latest edition). c) Manufacturer/supplier shall provide drawings indicating location and size of platforms and intermediate landings. See AWI 100 - Submittals Standard (latest edition) d) Manufacturer/supplier shall provide details and specifications of Product to ensure landing nosing and landing treads provided by others are compliant with approved submittals. e) Manufacturer/supplier shall provide documented instructions for Product installation which include anchorage and fastening methods and fastener details. f) Responsibility for materials and installation of platforms and intermediate landings shall be specified in contract documents. In the absence of specification, verification shall be obtained in writing prior to the commencement of work. 3.1.5 Default Grade Requirements a) Unless otherwise specified, Product shall comply with the minimum default Custom Grade.

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3.2 Material a) Materials used for construction of Product covered within the scope of this standard shall adhere to the requirements set forth in the AWI 300 - Materials Standard (latest edition). b) Materials used for the same purpose, within the scope of this standard, shall be consistent throughout a project. c) Sapwood and other characteristics are permitted where specified. d) For all materials selected for the manufacture of Product at transparent finishes: Premium Custom Economy Wormholes not Wormholes not exceeding 1.6 mm exceeding 1.6 mm [.063”] in diameter are [.063”] in diameter are permitted at a maximum permitted at a maximum Sapwood, wormholes, of one per linear 305 of two per linear 305 and knots are not mm [12”] mm [12”] permitted Permitted natural Permitted natural characteristics shall be characteristics shall be filled and sanded prior to filled and sanded prior to finishing finishing Slightly chipped grain, Streaks and sapwood A maximum of two streaks, and sapwood are permitted streaks are permitted in are permitted any tread provided they A maximum of one A maximum of one do not exceed 4.8 mm sound-tight knot not sound-tight knot not [.188”] in width by 152.4 exceeding 6.4 mm exceeding 6.4 mm mm [6”] in total [.250”] in diameter is [.250”] in diameter is combined length permitted per linear 914 permitted per linear 305 mm [36”] mm [12”] Lumber (including block segments or veneer of laminated material) are to be well matched for color and grain; sheet Material shall be Material shall be at the products shall be compatible for color and option of the compatible for grain manufacturer/supplier color with solid stock, and adjacent sheet products shall be well matched for color and grain

e) Materials selected for the manufacture of Product at opaque finishes shall meet requirements set forth in AWI 300 Materials (latest edition). f) Concealed surfaces shall permit aesthetic defects.

Proposed ANS AWI SMA 0643 – October 2020 DRAFT FOR REVIEW ONLY - DO NOT DISTRIBUTE g) Blocking, fillers, and shim stock shall be of sound material. h) Sealants and/or adhesives shall be compatible for color to adjacent surfaces. Sealants and/or adhesives shall be used in accordance with manufacturer/supplier’s documented instructions. i) All glue seams shall be tight and surface residue shall be completely removed. j) Where matching of “rustic” styles or finishes and/ or reclaimed materials is specified, number of permitted natural characteristics shall be as agreed to between owner/design professional and manufacturer/supplier. 3.2.1 Stairs, Components

3.2.1.1 Exposed Stringers and Skirt Boards a) Stringers shall be a minimum of 19.1 mm [.750”] thick. b) At stringers exceeding 4267 mm [168” long, joining for length is permitted. For exceptions, see Exceptions to Material Requirements herein. c) Wood selected to make up stringers shall be laid up, joined, and glued. Joinery shall be inconspicuous. d) Individual staves shall have a maximum of one end joint per 7315 mm [288”] and, at edge-glued stock (For exceptions, see Exceptions to Material Requirements herein): Premium Custom Economy There shall be no There shall be no Stringers shall be more than three more than five made up of staves staves per 305 mm staves per 305 mm no less than 50.8 [12”] in width [12”] in width mm [2”] in width Individual staves Individual staves Individual staves shall be at the shall be well- shall be compatible option of the matched for color for color and grain manufacturer/ and grain supplier e) At edge-glued stock, individual staves shall be lap jointed, finger jointed, doweled, or splined to achieve desired length. End joints in staves shall be staggered. f) At face laminated stringers, exposed plys at the edges shall be of same species. Face butt joints in exposed plys are permitted. g) At transparent finish, all visible staves shall be of same species or covered with matching veneer. h) Stringers shall be structurally sound, without splits or checks, and without knots within 50.8 mm [2”] of the edges. This requirement does not apply to non-structural skirt boards.

Proposed ANS AWI SMA 0643 – October 2020 DRAFT FOR REVIEW ONLY - DO NOT DISTRIBUTE

i) For edge gluing requirements see Exceptions to Material Requirements, Exposed Stringers and Skirt Boards.

3.2.1.2 Stringers, Concealed a) The following materials are permitted: Premium Custom Economy Engineered Material Engineered Material #1 common – glued laminated – glued laminated structural, fir, hem- timber (Glulam), timber (Glulam), fir, southern yellow laminated veneer laminated veneer pine (SYP) with no lumber (LVL), lumber (LVL), knots within 152.4 parallel strand parallel strand mm [6”] of bottom lumber (PSL) lumber (PSL) edge

3.2.1.3 Treads, Wood a) Shall be a minimum of 19.1 mm [.750”] thick. b) At glued-up stock: Premium Custom Economy Each tread shall Each tread shall Number and length consist of no more consist of no more of staves shall be at than three staves than five staves per the option of the per 305 mm [12”] in 305 mm [12”] in manufacturer/suppli width width er

Stave end joinery Stave end joinery Stave end joinery not permitted not permitted permitted

Individual staves Individual staves Individual staves shall be well- shall be compatible shall be compatible matched for color for color and grain for color and grain

c) Joinery shall be inconspicuous.

3.2.1.4 Treads, Hybrid a) Typically made of a solid wood of an economical species, joined by finger joints to a specified exposed wood end and return (See Figure 89). b) Use of hybrid treads at stairs with a runner or similar detail is permitted. c) Finger joints in hybrid treads are permitted only in that portion designed to be concealed (See Figure 89). d) Exposed tread material shall adhere to a minimum of Custom Grade material guidelines.

Proposed ANS AWI SMA 0643 – October 2020 DRAFT FOR REVIEW ONLY - DO NOT DISTRIBUTE

3.2.1.5 Treads, Engineered (Veneered) a) Shall have balanced veneer faces with a structurally sound substrate a minimum of 25.4 mm [1”] thick. b) Nosing edge shall be solid material a minimum of 31.75 mm [1.250”] wide and of the same species as veneer. c) Exposed ends shall be returned with the same species as veneer in order to completely conceal the substrate.

3.2.1.6 Treads, Plank (Slab) a) Defined as any tread 38.1 mm [1.500”] thick or greater. b) Exposed staves used to make plank treads shall be a minimum of 19.1 mm [.750”] thick and consist of full length staves joined and edge-glued. Joinery shall be inconspicuous. c) Order and thickness of staves shall be consistent throughout treads, platforms, and landings. d) Vertical staves or horizontal staves are permitted at manufacturer/supplier’s option.

3.2.1.7 Treads, Carpet Grade a) All treads that do not meet the requirements under any other subheading of this standard are considered carpet grade. b) Shall be a minimum of 19.1 mm [.750”] thick. c) Shall be solid wood or a minimum of sub-floor grade material that is structurally sound and designed specifically for carpeted applications. d) OSB treads are permitted, however, their use shall adhere to their intended manufacturing specification (e.g. indoor or outdoor applications). e) Up to four sound knots, not exceeding 38.1 mm [1.500”] in diameter are permitted at solid wood treads, provided they are not within 50.8 mm [2”] of the nosing edge. f) Finger joints are permitted.

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3.2.1.8 Treads, Landing a) Shall be fabricated of the same species as the adjacent treads and shall be: Premium Custom Economy Well-matched for Compatible for color At the option of color and grain to and grain to manufacturer/suppli adjacent treads and adjacent treads and er landing flooring landing flooring

b) At the exit of a flight, nosing of the landing tread shall be fabricated to match the thickness, profile, and projection of the nosing of the treads and landings throughout the stairway. c) At the exit of a flight, shall be set so the top surface is flush with flooring and is securely attached. d) Curved landing tread (See Figure 90) shall curve no greater than 45 degrees in a single section.

3.2.1.9 Treads, Ends a) At treads, ends shall: Premium Custom Economy Be returned to match the leading Be returned to edge of the tread match the leading Have profiled ends and conceal all edge of the tread to match the leading exposed end grain, and conceal end edge of the tread including end grain grain of the tread of the return

b) At winders in curved stairways shall have: Premium Custom Economy Returns at the Both edges Both edges option of the concentric with concentric with manufacturer/suppli curve of stair curve of stair er

3.2.1.10 Treads, Curved (Bowed) and Starting Steps a) Exposed end grain is permitted. Nosing profile shall be consistent. b) Grain shall be oriented to minimize end grain exposure at the path of travel.

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3.2.2 Risers a) Shall be a minimum of:

Premium Custom Economy 19.1 mm [.750”] 19.1 mm [.750”] 12.7 mm [.500”] thick thick thick

3.2.2.1 Risers, Transparent Finish a) At transparent finish risers:

Premium Custom Economy Shall have no more than two Shall have no more Shall have no more staves/veneer than three than four leaves per riser and staves/veneer staves/veneer shall be well- leaves per riser leaves per riser. matched for color and grain. Stave riser shall be well matched for Material shall be color and grain; Material shall be at compatible for color veneered riser shall the option of the and grain to be compatible for manufacturer/suppli adjacent surfaces color and grain with er within the stair. adjacent surfaces within the stair.

b) Joinery shall be inconspicuous.

3.2.2.2 Risers, Opaque Finish a) Edge gluing and finger joints are permitted. b) Filling and sanding of defects is permitted.

3.2.2.3 Risers, Curved (Bowed) or Starting Steps a) Species shall match in color and grain with risers within the flight per specified grade. b) Risers at curved or starting steps shall be: Premium Custom Economy Solid kerfed stock or Solid kerfed stock Kerfed or bending kerfed veneered with backer or solid plywood backer or plywood stock with form to maintain solid form to backer or solid form radius maintain radius to maintain radius

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3.2.4 Platforms and Intermediate Landings a) Defined as 38.1 mm [1.500”] thick or greater. b) Exposed staves used to make plank platforms/intermediate landings shall be a minimum of 19.1 mm [.750”] thick and consist of full length staves joined and edge-glued. Joinery shall be inconspicuous. c) Order and thickness of staves shall be consistent throughout treads, platforms, and landings. d) Staves shall be face glued or edge glued at manufacturer/supplier’s option. e) Expansion joints shall be used on platforms and intermediate landings to permit expansion and contraction. 3.2.5 Winders a) Grain shall run parallel to leading edge. b) Shall be of the same material and nosing profile as adjacent treads. 3.2.6 Guard and Handrail Components

3.2.6.1 Newels, Transparent Finish a) Veneered faces are permitted. b) At solid newels: Premium Custom Economy Staves shall be a Staves shall be a minimum of 19.1 minimum of 25.4 mm [.750”] thick mm [1”] thick and of and of the same the same species species at newels at newels 95.3 mm Staves shall be a 101.6 mm [4”] or [3.75”] or less minimum of 19.1 less mm [.750”] thick Staves shall be a Staves shall be a and of the same minimum of 31.8 minimum of 25.4 species mm [1.25”] thick at mm [1”] thick at newels exceeding newels exceeding 95.3 mm [3.75”] in 101.6 mm [4”] in diameter and be of diameter similar thickness Edge gluing is Edge gluing is permitted at center permitted at plys, Edge gluing is not plys, provided color provided color permitted remains compatible remains compatible after turning after turning Components shall Components shall Components shall be well-matched for be compatible for be compatible for color and grain color and grain color

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c) At box (hollow) newels: Premium Custom Economy Edge gluing of Edge gluing of faces is permitted faces is permitted at a maximum of Edge gluing of at a maximum of three staves per faces is permitted two staves per 203 152.4 mm [6”] or mm [8”] or wider. wider. Staves and sides Staves and sides Staves and sides shall be well- shall be compatible shall be compatible matched for color for color and grain for color and grain Corners shall be Corners shall be mitered or lap mitered or butted at Corners shall be jointed at the option the option of the mitered of the manufacturer/ manufacturer/ supplier supplier

d) Finger joints are not permitted. e) Solid squares are permitted if the surface and core moisture content are equal. f) Stile and rail construction of box newel sides with panels is permitted. g) Stile and rail construction of box newel sides with panels shall be compatible for color and grain.

3.2.6.2 Newels, Opaque Finish a) At opaque finish newels: Premium Custom Economy Edge gluing and Edge gluing and Edge gluing and finger joints are not finger joints are finger joints are permitted permitted. permitted. Filling and sanding Filling and sanding Filling and sanding of defects is not of defects is not of defects is permitted permitted permitted

h) Solid squares are permitted if the surface and core moisture content are equal. i) Stile and rail construction of box newel sides with panels is permitted.

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3.2.7 Handrails

3.2.7.1 Handrails, Straight

a) Shall be laminated to ensure straightness. b) Glue lines from horizontal plys shall not be visible from the top view of the rail. c) All visible plys shall be of the same species and grade. d) At straight handrails: Premium Custom Economy Finger joints are Rails not exceeding The top rail ply not permitted in the top 4724 mm [186”] exceeding 3556 mm rail ply at intervals long shall be all [140”] long shall be equal to or solid plys all solid exceeding 914mm [36”] long One staggered joint One staggered joint Staggered joints at is permitted at the is permitted at the top rail ply at the top rail ply top rail ply option of the exceeding 4724 mm exceeding 3556 mm manufacturer/suppli [186”] long [140”] long er Finger joints and Finger joints are Finger joints are edge gluing are not permitted at lower permitted at lower permitted plys plys Color of plys shall Plys shall be well- Plys shall be be at the option of matched in color compatible for color the manufacturer/ supplier

e) For individual material lengths by species, see Exceptions to Material Requirements herein.

3.2.7.2 Curved Handrails, Bending

a) Bending rails composed of vertical or horizontal plys are permitted. Number of plys is dependent on the radius, height, and width of the rail. b) Material shall be: Premium Custom Economy Well-matched for Compatible for color Compatible for color color and grain and grain

c) Lamination prior to resawing and profiling is permitted.

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d) Finger joints are permitted: Premium Custom Economy At vertical plys At vertical plys exceeding 4724 mm exceeding 3556 mm [186”] long [140”] long At the option of the At a maximum of At a maximum of manufacturer/ one per each ply one per each ply supplier exceeding 4724 mm exceeding 3556 mm [186”] long [140”] long

e) For individual material lengths by species, see Exceptions to Material Requirements herein. f) At outside vertical plys exceeding 4724 mm [186”] long, scarf joints are permitted.

3.2.7.3 Curved Handrails, Cut from Solid Blocks

a) Curved level rail shall be laminated with a minimum of 19.1 mm [.750”] thick plys. b) Individual segments that make up curved level rail segments shall be 45 degrees or less (See Figure 91). c) Solid stock or glued up block components shall be furnished in such sections as to avoid pronounced cross grain and reduce joints to a minimum. d) Curved rake rail shall have a minimum of 34.9 mm [1.375”] thick plys. No more than four plys are permitted to be visible on a section of rail. 3.2.8 Rail and Fitting Connections a) Shall be of same species. b) Shall be joined with glue and concealed hardware. 3.2.9 Tolerances

a) Factory machining tolerances for profiles of mating components shall not exceed .8 mm [.031”]. 3.2.10 Fittings a) Finger joints are:

Premium Custom Economy Permitted at lower Not permitted Not permitted plys of vertical drops of goosenecks

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b) Materials shall be furnished in such sections as to avoid pronounced cross grain and reduce joints to a minimum (See Figure 90). c) Grain shall be no greater than 45 degrees perpendicular to adjoining rails (See Figure 94). d) At fittings turning over 45 degrees, miter joints are permitted (See Figure 93). e) At volutes and turnouts, grain orientation of center ply shall be rotated slightly relative to top and bottom plys to minimize short grain instability (See Figure 95). f) Easings shall have a ply thickness to prevent exposure of glue lines at the top of the rail (See Figure 96). g) Wreathed transitions shall have a minimum of 34.9 mm [1.375”] thick plys. 3.2.11 Guard In-Fill

3.2.11.1 Wood Balusters, Transparent Finish

a) At transparent finish wood balusters: Premium Custom Economy Components shall be Components shall be Components shall be composed of one composed of one composed of one solid piece where not solid piece where not solid piece where not exceeding 50.8 mm exceeding 44.5 mm exceeding 31.8 mm [2”] thick [1.750”] thick [1.250”] thick Turned and flat Turned and flat Sanding shall be at sections shall be sections shall be the option of the sanded prior to sanded prior to manufacturer/supplier finishing finishing

3.2.11.2 Wood Balusters, Opaque Finish

a) Glued up squares are permitted and: Premium Custom Economy

Finger joints are not Staggered finger Staggered finger permitted joints are permitted joints are permitted

3.2.11.3 Wood, Other Wood In-Fill

a) Wood in-fill shall be compatible with design and specification of other components within guard and stair systems. Species specification shall be in accordance with AWI 300 – Materials Standard (latest edition).

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3.2.11.4 Balusters, Metal

a) Shall be: Premium Custom Economy Solid bar construction Solid bar construction Hollow bar or a hollow tube with or a hollow tube with construction with wall wall thickness of a wall thickness of a thickness between minimum of 1.2 mm minimum of 1.2 mm 1.2 mm [.047”] and .8 [.047”] [.047”] mm [.031”]

3.2.11.5 Cable Rail Systems

a) Components shall be of material appropriate to their intended application (i.e. of the correct material or alloy). If stainless steel is used as a part of cable rail systems, a minimum of type 304 is required. b) Components in direct contact with one another shall be of the same material to prevent galvanic corrosion. c) The parts and materials in the cable rail system shall be consistent throughout the project to ensure adherence to mechanical requirements and design intent. d) Cable strand count and configuration shall allow for manufacturer/supplier’s recommended tensioning without undue stretching and sagging.

3.2.11.6 Glass In-Fill

a) Glass used for in-fill shall be in accordance with ANSI Z97.1 (latest edition) and ASTM C1036 (latest edition) Standard Specification for Flat Glass. b) All glass in a stair system shall be made using the same manufacturing process and from the same batch, whenever possible, to prevent differences in color and clarity. c) All edge treatments and polishing of glass panels shall be consistent throughout the stair system. d) Glass mounting systems using metal to metal connections (i.e. glass clamps with metal posts) shall be of the same material to prevent galvanic corrosion. e) Material used for mounting glass panels shall be appropriate for the intended application (i.e. indoor vs outdoor or wood mount vs concrete)

3.2.11.7 Metal In-Fill

a) Shall be compatible with other components within the guard system.

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3.2.12 Well-Hole Trim

a) Material, such as nosing, fascia, scotia, curbing, caps, and shoe rail shall be compatible with other materials used in the stair and guard systems.

3.2.12.1 Nosing, Well-Hole

a) Well-hole nosing shall be made of the same species as the adjacent treads, and/or landing tread. b) Well-hole nosing shall be made to match the thickness, profile, and projection of the treads and/or landing tread throughout the stair. c) Curved well-hole nosing shall curve no greater than 45 degrees in a single section. d) Curved well-hole nosing shall be furnished in such sections as to avoid pronounced cross grain and reduce joints to a minimum. e) Material for well-hole nosing shall be: Premium Custom Economy Well-matched for color Compatible for color At the option of and grain to adjacent and grain to adjacent manufacturer/supplier treads and landing tread treads and landing tread

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3.3 Structural a) Residential stairways, handrails, and guard systems in one- or two-family homes of no more than three stories with separate means of egress shall be built as designed by the engineer of record or in accordance with the design approved by the authority having jurisdiction to enforce the applicable code of the jurisdiction. Where no code exists and/or is enforced, the design shall comply with the live load requirements specified in the International Residential Code (latest edition) as published by the International Code Council. b) Residential and other stairways, handrails, and guard systems in all other occupancies shall be built as designed by the engineer of record or in accordance with the design approved by the authority having jurisdiction to enforce the applicable code of the jurisdiction. Where no code exists and/or is enforced the design shall comply with the live load requirements in the International Building Code (latest edition) as published by the International Code Council.

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3.4 Aesthetic a) Tolerances for defects shall be in accordance with AWI 300 - Materials Standard. b) Where matching of “rustic” styles or finishes and/ or reclaimed materials is specified, number of permitted natural characteristics shall be as agreed to between owner/design professional and manufacturer/supplier. c) Residual marks, including adhesive and filler residue, on exposed and semi- exposed surfaces shall be removed. d) Fasteners shall be concealed e) Fastener holes in pre-finished Product 4.8 mm [.188”] or smaller shall be filled by the installer with matching filler (putty) furnished by the manufacturer/supplier. f) Plugs are permitted provided they are sanded flush and compatible for color, grain, and grain direction. g) Fastener holes in Product larger than 4.8 mm [.188”] shall be filled by the installer with plugs furnished by the manufacturer/supplier. h) Unless otherwise indicated within this standard, Product shall be installed free of open joints, visible machine marks, cross sanding (excluding turned surfaces), tear-out, nicks, chips, scratches, layout lines, pencil lines, and/or natural defects exceeding the quantity and/or size limits defined in the AWI 300 - Materials Standard (latest edition). i) Exposed surfaces of all materials shall be free of tooling and chatter marks and sanded to a minimum of: Premium Custom Economy

150-grit finish 120-grit finish 100-grit or 15 KMPI

j) Wood selected to make up components shall be joined and glued. Joinery shall be inconspicuous. k) Reveals shall be consistent between like parts throughout the system. l) Profiles used for the same purpose, within the scope of this standard, shall be consistent throughout a project. m) Telegraphing is not permitted.

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3.4.2 Transparent Finish a) Shall be finished with a finishing technology (See AWI Finishing Standard, latest edition) of the manufacturer/supplier’s choice. b) Exposed faces: Premium Custom Economy Shall be well- Shall be compatible Shall be compatible matched for color and for color and grain for color between like grain between like between like and and adjacent and adjacent adjacent components components of the components of the of the same material same material same material

3.4.3 Opaque Finish

a) Shall be finished with a finishing technology (See AWI Finishing Standard, latest edition) of the manufacturer/supplier’s choice. b) All defects in exposed faces shall be repaired, filled, and sanded before painting. 3.4.4 Stringers, Glued up

a) Exposed plys within stringers shall be of similar thickness. b) Face plys shall be consistent between like parts within the stair. c) Butt joints of plys in a stringer shall be staggered. d) Stringer plys shall be glued and clamped to provide tight and flush joints.

e) For edge gluing requirements see Exceptions to Material Requirements, Exposed Stringers and Skirt Boards. 3.4.5 Treads (Including Winders)

a) Nosing projections and profiles shall be consistent throughout the stairway. b) Grain shall run parallel to the leading edge of the tread.

3.4.5.1 Treads, Returned a) Tread ends shall: Premium Custom Economy Be returned to match the leading Be returned to edge of the tread match the leading Have profiled ends and conceal all edge of the tread match the leading exposed end grain, and conceal end edge of the tread including end grain grain of the tread of the return

19 Proposed ANS AWI SMA 0643 – October 2020 DRAFT FOR REVIEW ONLY - DO NOT DISTRIBUTE

b) Shall be securely attached to ensure a tight fit to the end of the tread. Gaps shall not exceed 20 percent of the joint perimeter and shall not exceed: Premium Custom Economy .4 mm [.016”] .4 mm [.016”] .8 mm [.031”]

c) Shared surfaces of tread and return shall be sanded flush. d) Grain orientation of curved returns shall: Premium Custom Economy Minimize exposed Minimize exposed Be at the option of end grain on the end grain on the the manufacturer/ edge edge supplier

e) Returned ends of winders in curved stairways shall: Premium Custom Economy Have both edges of Have both edges of Be at the option of the return the return the manufacturer/ concentric with concentric with supplier curve of stair curve of stair

3.4.5.2 Treads, Spiral (Unsupported by Riser)

a) Grain direction shall (See Figure 98): Premium Custom Economy

Run parallel to the Be at the option of Be at the option of leading and trailing the manufacturer/ the manufacturer/ edge of the tread supplier supplier

3.4.5.3 Treads and Landings, Plank (Slab) a) Exposed end grain is permitted. 3.4.6 Risers a) Shall be a minimum of: Premium Custom Economy 19.1 mm [.750”] thick 19.1 mm [.750”] thick 12.7 mm [.500”] thick

3.4.6.1 Risers, Curved (Bowed) or Starting Steps

a) Telegraphing caused by kerfing is not permitted. b) Where available material lengths require construction to be of multiple components, joints in face material shall be inconspicuous.

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3.4.7 Guard and Handrail Components

3.4.7.1 Newels

a) At connections to stair components other than rails, gaps shall not exceed: Premium Custom Economy .8 mm [.031”] .8 mm [.031”] 1.6 mm [.063”]

3.4.7.2 Handrails

a) All rail to rail and rail to fitting joints shall be sanded and/or sculpted for seamless profile alignment to the following flushness tolerances: Premium Custom Economy .4 mm [.016”] .4 mm [.016”] .8 mm [.031”]

b) At rail to newel, rail to rail, and rail to fitting, gaps (See Figure XXXX) shall not exceed 20 percent of the joint perimeter and shall not exceed: Premium Custom Economy .4 mm [.016”] .4 mm [.016”] .8 mm [.031”]

3.4.8 Fittings

3.4.8.1 Fittings, Transparent Finish

a) Fitting material shall be: Premium Custom Economy Compatible for color Compatible for color within fitting within fitting At the option of the Compatible for color Compatible for color manufacturer/ with adjacent with adjacent supplier components components

b) Finger joints are: Premium Custom Economy Permitted at lower plys of vertical Not permitted Not permitted drops of goosenecks

c) Countersunk metal splines are permitted, provided the slots have been filled and sanded flush.

3.4.8.2 Fittings, Opaque Finish

a) Shall be closed-grained wood.

b) Plugs at joints are permitted provided they are sanded flush.

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c) Countersunk metal splines are permitted, provided the slots have been filled and sanded flush.

3.4.9 Guard, In-Fill

3.4.9.1 Wood Balusters and Wood In-Fill Joinery, Transparent and Opaque Finish

a) At round end (no shoulder) in drilled holes, gaps shall not exceed: Premium Custom Economy .4 mm [.016”] .8 mm [.031”] 1.6 mm [.063”]

b) At round or square end (with shoulder), where not in plow, gaps shall not exceed: Premium Custom Economy .4 mm [.016”] .8 mm [.031”] .8 mm [.031”]

c) At square end in plow with fillet, gaps shall not exceed: Premium Custom Economy .8 mm [.031”] .8 mm [.031”] 1.6 mm [.063”]

d) All joints in wood in-fill panels and panel systems shall be smooth and flush.

3.4.9.2 Balusters and Newels, Metal

a) Metal balusters and newels with shoes shall have: Premium Custom Economy Epoxy shoe Epoxy shoe centered on centered on Shoes at the option baluster or newel baluster or newel of the manufacturer/ and fit to match and fit to match supplier pitch of stair pitch of stair Set screws are permitted at the Set screws not Set screws not option of the permitted permitted manufacturer/ supplier

c) Metal balusters and newels without shoes shall be: Premium Custom Economy At the option of the Mortised to fit end Mortised to fit end manufacturer/ of baluster or newel of baluster or newel supplier

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3.4.9.3 Cable In-Fill

a) All fitting and hardware components shall have compatible finish.

b) Exposed cable ends are not permitted.

c) All sections of cable in-fill shall be tensioned equally.

d) Where cables pass through wood posts at vertical or horizontal transitions, post protectors shall be used.

e) Spreader bars shall be spaced equally and securely attached.

f) Bushings shall be used to isolate reactive materials and prevent electrolysis.

3.4.9.4 Glass In-Fill/Guards

a) All hardware components shall have compatible finish.

b) All glass shall be compatible in appearance.

3.4.10 Metal In-Fill/Guards a) At round end in drilled holes, gaps shall not exceed: Premium Custom Economy .8 mm [.031”] .8 mm [.031”] 1.6 mm [.063”]

b) Where not in plow and without shoes, gaps shall not exceed: Premium Custom Economy 1.6 mm [.063”] 1.6 mm [.063”] 2.4 mm [.094”]

c) Where in plow, gaps shall not exceed: Premium Custom Economy 1.6 mm [.063”] 1.6 mm [.063”] 2.4 mm [.094”]

d) Metal in-fill balusters with shoes shall have: Premium Custom Economy Epoxy shoe centered Epoxy shoe centered Shoes at the option on baluster or newel on baluster or newel of the and fit to match pitch and fit to match pitch manufacturer/supplier of stair of stair Set screws are Set screws not Set screws not permitted at the permitted permitted option of the manufacturer/supplier

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e) Metal in-fill balusters without shoes shall be securely attached and: Premium Custom Economy Mortised at the option Mortised to fit ends Mortised to fit ends of the manufacturer/supplier

3.4.11 Well-Hole Trim

a) Outside corners shall be mitered.

b) Moulded components at inside corners shall be: Premium Custom Economy Coped Coped Mitered or coped

c) S4S at inside corners shall be butted.

d) Joinery of well-hole trim requires: Premium Custom Economy Exposed trimmed Exposed trimmed ends Exposed trimmed ends shall be miter ends at the option of shall be profiled or returned the installer miter returned Multiple joints in Multiple joints in Multiple joints in running trim shall not running trim shall not running trim shall not be within 1219 mm be within 914 mm be within 610 mm [48”] of another joint [36”] of another joint [24”] of another joint in the run, including in the run, including in the run, including corners corners corners

f) Exposed fasteners shall be inconspicuous.

g) Exposed fasteners shall be countersunk through the exposed material surface, kept to a minimum, and shall be: Premium Custom Economy Fastened in Set in quirks and Set in quirks and placement at the reliefs where possible reliefs where possible option of the installer

3.4.12 Nosing, Well-Hole

a) Nosing of landing tread, at the exit of a flight, shall be made to match the thickness, profile, and projection of the treads throughout stairway.

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3.4.14 Staircase (Assembled Unit)

3.4.14.1 Stairs, Open-Cut Stringer a) Stairs at open-cut stringers or skirt boards shall: Premium Custom Economy Attachment of risers at the option Be mitered to Be mitered to of the risers. risers. manufacturer/ supplier

b) Treads at open-cut stringers shall: Premium Custom Economy Have tread return Have tread return nosing applied with nosing applied no visible fasteners Have end of tread Have end of tread profiled or applied return nosing tread return nosing Have end of tread profiled with visible at the option of the return nosing end grain at the manufacturer/ returned with no option of the supplier end grain visible manufacturer/ supplier c) Brackets at open-cut stringers shall be mitered to risers. d) Tread returns shall be cut to eliminate end grain at the front edge.

3.4.14.2 Stairs, Closed Stringer or Open-Closed Stringer

a) At closed stringers: Premium Custom Economy Treads and risers Treads and risers Butt joints are shall be mortised shall be mortised permitted into stringers into stringers

b) Knee walls shall be capped.

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3.5 Fabrication

a) Mechanical fasteners, except for nails, at exposed faces shall be concealed.

3.5.1 Stringers

3.5.1.1 Stringers, Mortised a) Mortise depth shall be a minimum of 6.4 mm [.250”] to facilitate securing of the wedge, tread, and/or riser, as applicable (See Figure 97-A). b) At open mortised (wedged) stringers, tread/riser/stringer joint gap shall be a maximum of .4 mm [.016”]. Gaps shall not exceed 20 percent of the joint perimeter (See Figure 97-B). c) At nosing, joint gap shall be a maximum of .8 mm [.031”] (See Figure 97-C). d) Treads and risers that are mortised into open mortised stringers shall be securely attached with wedges, glue, and/or mechanical fasteners (See Figure 97-D). e) At closed mortise (no wedge) stringers, tread/riser/stringer joint gap shall not exceed (See Figure 97-E): Premium Custom Economy

.4 mm [.016"] .8 mm [.031"] 1.2 mm [.047"]

f) Treads and risers that are mortised into closed mortised stringers shall be securely attached with glue and mechanical fasteners (See Figure 88).

3.5.1.2 Stringers, Open Cut a) Shall be securely attached to underside of treads with glue blocks and/or pocket screws. b) Shall be mitered to risers with no visible end grain and no gap in the miter joints. c) At risers with transparent finish, miter joints shall be glued and fasteners shall be concealed whenever possible.

3.5.1.3 Stringer Transitions a) Shall allow for continuation, return, or termination of base cap (See Figure 100).

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3.5.2 Risers a) Tread/top and bottom of riser joint gap shall not exceed: Premium Custom Economy .3 mm [.012”] wide by .4 mm [.016”] wide by .8 mm [.031”] wide by 20% of the joint 20% of the joint 20% of the joint length length length

b) Where scotia is used, gap tolerance shall be measured between tread and scotia. c) Shall be securely attached to the leading edge of the tread with mechanical fasteners and/or glue blocks. d) Shall be securely attached to the trailing edge of the tread with mechanical fasteners. 3.5.3 Treads a) Shall be securely attached to stringers and risers with mechanical fasteners, wedges, and/or glue blocks. b) At open rise stairs, plank treads shall be attached to stringers with mechanical fasteners. 3.5.4 Stair Carriages (Concealed Stringers) a) Shall be securely attached to the staircase assembly. b) Shall be securely attached to the building structure.

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3.6 Installation a) Installer shall obtain, review, and comply with manufacturer/supplier’s documented instructions for installation. Product shall be securely attached. Contract documents regarding installation method(s) shall supersede manufacturer/supplier’s directive unless design professional’s approval to deviate is provided in writing. b) Prior to commencement of installation, installer shall confirm the presence of wood blocking or metal strapping as indicated in contract documents. Installer shall confirm that field conditions and dimensions, including the elevation of landings and floors, are as indicated in the contract documents. If documented conditions are not met, written directives shall be obtained from the design professional prior to proceeding with installation. c) It is not the responsibility of the installer to scribe or fit to walls, ceilings, floors, or openings whose plumb, level, flat, straight, or square values exceed tolerances specified in contract documents. In absence of specification, floor, wall, ceiling, and/or opening variations in excess of 6.4 mm [.250”] in 2438 mm [96”] of being plumb, level, flat, straight, square, or of the correct size are not acceptable for the installation of Product. d) The types of joinery used shall be consistent throughout the stairway. e) Drywall and bugle head screws are not permitted for the installation of Product. f) Fasteners shall be concealed g) Fastener holes in pre-finished Product 4.8 mm [.188”] or smaller shall be filled by the installer with matching filler (putty) furnished by the manufacturer/supplier. h) Plugs are permitted provided they are sanded flush and compatible for color, grain, and grain direction. i) Fastener holes in Product larger than 4.8 mm [.188”] shall be filled by the installer with plugs furnished by the manufacturer/supplier. j) Installation shall comply with the Product’s aesthetic grade as specified in the contract documents. k) Product shall be installed plumb and level within 3.2 mm [.125”] in 2438 mm [96”]. l) When factory-finished Product is cut or modified to facilitate installation, the resulting unfinished core shall be sealed prior to installation. m) Tolerances listed for gaps and flushness apply to Product as installed. n) Unless otherwise indicated within this standard, Product shall be installed free of open joints, visible machine marks, cross sanding, tear-out, nicks, chips, scratches, layout lines, pencil lines, and/or natural defects exceeding the quantity and/or size limits defined in the AWI 300 - Materials Standard (latest edition).

Proposed ANS AWI SMA 0643 – October 2020 DRAFT FOR REVIEW ONLY - DO NOT DISTRIBUTE o) Plank (slab) platforms shall be installed with expansion joints to permit expansion and contraction. p) Tolerances for running trim not specified below shall be in accordance with the general tolerances indicated in AWI 0620 - Finish Carpentry/Installation (latest edition). q) All pre-manufactured cable components and/or hardware shall be installed in accordance with manufacturer/supplier’s documented instructions for assembly and installation. r) All pre-manufactured glass components and/or hardware shall be installed in accordance with manufacturer/supplier’s documented instructions for assembly and installation. s) Residual marks, including adhesive and filler residue on exposed or semi- exposed faces, shall be removed. t) Areas of installation shall be left broom clean. Debris shall be removed and disposed of in containers provided by the contractor or construction manager. 3.6.1 Field Assembled Stair Components a) Gap tolerances between exposed skirt boards, treads, and risers shall not exceed: Premium Custom Economy .8 mm [.031”] 1.2 mm [.047”] 1.6 mm [.063”]

b) Concealed stringer fasteners to wall shall be located no less than 50.8 mm [2”] from the bottom edge and no more than 610 mm [24”] on center measured horizontally.

3.6.1.1 Routed Stringers, Field Assembled a) Shall be securely attached to the building structure. b) Where fastened to wall, shall be securely attached to wall no more than 610 mm [24”] on center measured horizontally. c) Treads and risers that are mortised into stringers shall be securely attached with wedges, glue, and/or mechanical fasteners. d) At open mortised (wedged) stringers, tread/riser/stringer joint gap shall be a maximum of .4 mm [.016”]. e) At nosing, joint gap shall be a maximum of .8 mm [.031”]. f) Mortise depth shall be a minimum of 6.4 mm [.250”] to facilitate securing of the wedge, tread, and riser.

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g) At closed mortise (no wedge) stringers, tread/riser/stringer joint gap shall not exceed (See Figure 88):

Premium Custom Economy

.4 mm [.016"] .8 mm [.031"] 1.2 mm [.047"]

3.6.1.2 Open Cut Stringers a) Shall be securely attached to underside of treads with glue blocks and/or pocket screws. b) Shall be mitered to risers with no visible end grain and no gap in the miter joints. c) At risers with transparent finish, miter joints shall be glued and fasteners shall be concealed whenever possible.

3.6.1.3 Stringer Transitions a) Shall allow for continuation, return, or termination of base cap (See Figure 100).

3.6.1.4 Risers a) Tread/top and bottom of riser joint gap shall not exceed: Premium Custom Economy .4 mm [.016”] .8 mm [.031”] 1.2 mm [.047”]

b) Gap tolerance shall be measured between tread and scotia when scotia is used. c) Shall be securely attached to the leading edge of the tread with mechanical fasteners and/or glue blocks and may include groove and rabbet joints. d) Shall be securely attached to the trailing edge of the tread with mechanical fasteners and may include groove and rabbet joints.

3.6.1.5 Treads a) Shall be securely attached to stringers and risers with mechanical fasteners, wedges, and/or glue blocks. b) At open rise stairs, plank treads shall be attached to stringers with mechanical fasteners.

3.6.1.6 Stair carriages (concealed stringers) a) Shall be securely attached to the staircase assembly. b) Shall be securely attached to the building structure.

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3.6.2 Stairs, Shop Assembled a) Stair units shall be wrapped to protect stringer, riser, and tread exposed surfaces from handling and jobsite traffic when installation prior to application of wall finish is required.

3.6.2.1 Attachment to the Structure/Stringers, Concealed a) Stringers shall be securely attached to the building structure with fasteners that are not subject to withdrawal. When installed prior to wall finish, stringers shall be spaced off the framing as required. b) Fasteners shall be located no less than 50.8 mm [2”] from the bottom edge and no more than every 610 mm [24”] on-center measured horizontally. c) Ends of stringers shall be supported by the floor structure so as to prevent splitting using ledgers and/or mechanical connectors as necessary. The ends of stringers not supported by walls shall be connected to prevent rotation at the connection. d) The top and bottom riser heights shall be consistent with the other risers of the flight and the landing tread shall be flush with the finished floor at the top of the flight. e) Multiple flights in a stairway shall be positioned to align with stairway and/or building structure(s)and any guard and/or handrail requirements in accordance with the approved manufacturer/supplier submittals. 3.6.3 Guard and Handrail Installation a) Product shall be installed in accordance with structural and aesthetic requirements set forth within this standard. b) Guards and/or handrails shall be securely attached to remain secure and prevent compression of wall finish material (e.g. gypsum wallboard, drywall, etc.) (See Figure 99).

3.6.3.1 Newels a) At connections to stair components other than rails, gaps shall not exceed: Premium Custom Economy .8 mm [.031”] .8 mm [.031”] 1.6 mm [.063”]

b) At newel to rail, gaps shall not exceed 20 percent of the joint perimeter and gaps shall not exceed: Premium Custom Economy .4 mm [.016”] .4 mm [.016”] .8 mm [.031”]

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3.6.3.2 Handrails a) All rail to rail and rail to fitting joints shall be sanded and/or sculpted for seamless profile alignment to the following flushness tolerances: Premium Custom Economy .4 mm [.016”] .4 mm [.016”] .8 mm [.031”]

b) At rail to newel/rosette/wall termination, rail to rail, rail to fitting, gaps shall not exceed 20 percent of the joint perimeter and gaps shall not exceed: Premium Custom Economy .4 mm [.016”] .4 mm [.016”] .8 mm [.031”]

3.6.4 Fittings a) Visible fasteners are not permitted unless specified.

b) Countersunk metal splines are permitted, provided the slots have been filled and sanded flush.

3.6.4.1 Fittings, Transparent Finish a) Grain and color, unless otherwise specified, shall be: Premium Custom Economy Well-matched for Compatible for Compatible for grain and color grain and color color

b) Finger joints are: Premium Custom Economy Permitted at lower plys of vertical Not permitted Not permitted drops of goosenecks

3.6.4.2 Fittings, Opaque Finish a) At opaque finish, fittings shall be closed-grained wood. b) Plugs at joints are permitted provided they are sanded flush.

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3.6.5 Guard, In-Fill

3.6.5.1 Wood Balusters and Wood In-Fill Joinery, Transparent and Opaque Finish a) At round end (no shoulder) in drilled holes, gaps shall not exceed:

Premium Custom Economy .8 mm [.031”] .8 mm [.031”] 1.6 mm [.063”]

b) At round or square end (with shoulder), where not in plow, gaps shall not exceed: Premium Custom Economy .4 mm [.016”] .8 mm [.031”] .8 mm [.031”]

c) At square end in plow with fillet, gaps shall not exceed: Premium Custom Economy .8 mm [.031”] .8 mm [.031”] 1.6 mm [.063”]

d) All joints in wood in-fill panels and panel systems shall be smooth and flush.

3.6.5.2 Balusters and Newels, Metal a) Metal balusters and newels with shoes shall have: Premium Custom Economy Epoxy shoe Epoxy shoe Shoes at the option centered on centered on of the baluster or newel baluster or newel manufacturer/ and fit to match and fit to match supplier pitch of stair pitch of stair Set screws are permitted at the Set screws not Set screws not option of the permitted permitted manufacturer/ supplier

b) Metal balusters and newels without shoes shall be: Premium Custom Economy At the option of the Mortised to fit end Mortised to fit end manufacturer/ of baluster or newel of baluster or newel supplier

3.6.5.3 Cable In-Fill a) Exposed cable ends are not permitted. b) All sections of cable in-fill shall be tensioned equally.

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c) Where cables pass through wood posts at vertical or horizontal transitions, post protectors shall be used. d) Spreader bars shall be spaced equally and securely attached. e) Bushings shall be used to isolate reactive materials and prevent electrolysis.

3.6.5.4 Glass In-Fill/Guards a) Hardware and glass for glass infill/guards shall be installed per manufacturer/ supplier’s specifications. b) Metal In-Fill/Guards a) At round end in drilled holes, gaps shall not exceed: Premium Custom Economy .8 mm [.031”] .8 mm [.031”] 1.6 mm [.063”]

b) Where not in plow and without shoes, gaps shall not exceed: Premium Custom Economy 1.6 mm [.063”] 1.6 mm [.063”] 2.4 mm [.094”]

c) Where in plow, gaps shall not exceed: Premium Custom Economy 1.6 mm [.063”] 1.6 mm [.063”] 2.4 mm [.094”]

d) Metal in-fill balusters with shoes shall have: Premium Custom Economy Epoxy shoe Epoxy shoe Shoes at the option centered on centered on of the baluster or newel baluster or newel manufacturer/ and fit to match and fit to match supplier pitch of stair pitch of stair Set screws are permitted at the Set screws not Set screws not option of the permitted permitted manufacturer/ supplier

e) Metal in-fill balusters without shoes shall be: Premium Custom Economy Fastened in placement at the Mortised to fit end Mortised to fit end option of the of baluster or newel of baluster or newel manufacturer/ supplier

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3.6.5.5 Well-Hole Trim a) Outside corners shall be mitered. b) Moulded components at inside corners shall be: Premium Custom Economy Coped Coped Mitered or coped

c) S4S at inside corners shall be butted. d) Joinery of well-hole trim requires: Premium Custom Economy Exposed trimmed Exposed trimmed ends Exposed trimmed ends shall be miter ends at the option shall be profiled or returned of the installer miter returned Multiple joints in Multiple joints in Multiple joints in running trim shall running trim shall running trim shall not be within 1219 not be within 914 not be within 610 mm [48”] of another mm [36”] of another mm [24”] of another joint in the run, joint in the run, joint in the run, including corners including corners including corners

e) Fasteners and fastening include the use of finish nails, trim screws, staples, pins, and/or construction adhesive for inconspicuous fastening. Staples with a crown exceeding 4.8 mm [.188”] wide are not permitted. f) Exposed fasteners shall be inconspicuous. g) Exposed fasteners shall be countersunk through the exposed material surface, kept to a minimum, and shall be: Premium Custom Economy Fastened in Set in quirks and Set in quirks and placement at the reliefs where reliefs where option of the possible possible installer

3.6.5.6 Nosing, Well-Hole a) Landing tread shall be installed flush with flooring at all flight exits. b) Shall be installed in accordance with approved manufacturer/supplier submittals.

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4.0 Figures / Illustrations

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5.0 Supplemental Information 5.1 Glossaries a) The Architectural Woodwork Institute glossary can be found at: https://www.awinet.org/standards/glossary b) The Stairbuilders and Manufacturers Association Glossary of Stair Terminology can be found at: http://stairways.org/awismastandard 5.2 Design Professional Responsibilities a) The authority having jurisdiction for enforcement of the applicable building code shall be stated in contract documents by the design professional. 5.3 Surface Categories 5.3.1 Exposed a) Defined as all exterior and interior surfaces exposed to view. 5.3.2 Semi-Exposed a) Defined as surfaces that are generally neither visible nor accessible to the building occupants and/or general public but can be made visible or accessible by the movement of a component. 5.3.3 Concealed a) Defined as surfaces that are neither visible nor accessible to the building occupants and/or general public under normal circumstances. 5.4 SMA Supplemental Documents a) SMA provides additional resources for stair manufacturers, engineers, and design professionals at https://stairways.org/awismastandard b) Some of the documents included are:

 SMA Visual Interpretations of the International Residential Code

 Mississippi State University Design Values Report Summary

 Design Values for Domestic Wood Species Used in Stairway Construction

 Physical and Mechanical Properties of Clear Wood from Red Oak and White Oak 5.5 References a) AMP 500 - Metal Finishes Manual (latest edition) b) AMP 555 - Code of Standard Practice for the Architectural Metal Industry (latest edition) c) ANSI Z97.1 (latest edition) d) ANSI/AWI 0620 - Finish Carpentry/Installation (latest edition)

Proposed ANS AWI SMA 0643 – October 2020 DRAFT FOR REVIEW ONLY - DO NOT DISTRIBUTE

e) ASTM C1036 (latest edition) f) AWI 100 - Submittals (latest edition) g) AWI 200 - Care & Storage (latest edition) h) AWI 300 - Materials (latest edition) i) AWI Finishing Standard (latest edition) j) International Residential Code (latest edition) 5.6 Exceptions to Material Requirements a) The following species are subject to the requirements of 3.2 Material unless otherwise indicated in the tables below: Alder (Red), Anigre, Ash (White), Basswood, Beech (American), Beech (European), Birch (Yellow – natural), Birch (Yellow - select red), Birch (Yellow - select white), Cedar (Western Red), Cherry (American Black), Fir (Douglas - flat grain), Fir (Douglas - vertical grain), Hickory (True Group), Mahogany (African - plain sawn), Mahogany (African - quarter sawn), Mahogany (American), Makore, Maple (Hard – natural), Maple (Hard - select white), Maple (Soft – natural), Oak (English Brown), Oak (Red - plain sawn), Oak (Red - rift sawn), Oak (Red - quarter sawn), Oak (White - plain sawn), Oak (White - rift sawn), Oak (White - quarter sawn), Pecan Group (Hickory), Pine (Eastern or Northern White), Pine (Ponderosa), Pine (Southern Yellow), Pine (Sugar), Poplar (Yellow), Redwood (flat grain heartwood), Redwood (vertical grain heartwood), Teak, Jatoba, Sapele, and Walnut (American Black).

WOOD SPECIES EXPOSED STRINGERS & SKIRT BOARDS Maximum Number of Staves Per 12” Width

Premium Custom Economy Cherry, American Black 4 S S Oak, English Brown 4 S S Oak, Red - rift sawn 4 S S Oak, Red - quarter sawn 4 S S Oak, White - rift sawn 4 S S Oak, White - quarter sawn 4 S S Pecan Group, Hickory 4 S S Walnut, American Black 4 S S *S - Requirements set forth in AWI/SMA 0643 - Wood Stair, Handrail, and Guard Systems (latest edition) shall apply

Proposed ANS AWI SMA 0643 – October 2020 DRAFT FOR REVIEW ONLY - DO NOT DISTRIBUTE

WOOD SPECIES EXPOSED STRINGERS AND SKIRT BOARDS Minimum Length Number of Linear Splices in of Stave Where

Staves up to 14’ One-Piece Stave is Required Premium Custom Economy All Grades Alder, Red 1 1 Unlimited 10’ Anigre 1 1 Unlimited 12’ Ash, White 1 1 Unlimited 12’ Basswood 1 1 Unlimited 10’ Beech, American 1 1 Unlimited 12’ Beech, European 0 0 Unlimited 15’-6” Birch, Yellow - natural 1 1 Unlimited 12’ Birch, Yellow - select red 1 1 Unlimited 11’ Birch, Yellow - select white 1 1 Unlimited 11’ Cedar, Western Red 0 0 Unlimited 15’-6” Cherry, American Black 1 2 Unlimited 7’ Fir, Douglas - flat grain 0 0 Unlimited 15’-6” Fir, Douglas - vertical grain 0 0 Unlimited 15’-6” Hickory, True Group 1 1 Unlimited 12’ Mahogany, African - plain sawn 0 0 Unlimited 15’ Mahogany, African - quarter 0 0 Unlimited 15’ sawn

Proposed ANS AWI SMA 0643 – October 2020 DRAFT FOR REVIEW ONLY - DO NOT DISTRIBUTE

WOOD SPECIES RAIL Minimum Length of Rail where Solid Top Cap is Required

Premium Custom Economy Alder, Red 10’ 8’ S Anigre 12’ 10’ S Ash, White 12’ 10’ S Basswood 12’ 10’ S Beech, American 12’ 10’ S Beech, European 15’-6” 14’ S Birch, Yellow - natural 12’ 10’ S Birch, Yellow - select red 11’ 10’ S Birch, Yellow - select white 11’ 10’ S Cedar, Western Red 15’-6” 14’ S Cherry, American Black 8’ 6’ 4’ Hickory, True Group 12’ 10’ 8’ Makore 12’ 10’ 8’ Oak, English Brown 8’ 6’ 4’ Oak, Red - rift sawn 10’ 8’ 4’ Oak, Red - quarter sawn 10’ 8’ 4’ Oak, White - rift sawn 10’ 8’ S Oak, White - quarter sawn 10’ 8’ S Teak 10’ 8’ 4’ Walnut, American Black 8’ 6’ 4’ *S - Requirements set forth in AWI/SMA 0643 - Wood Stair, Handrail, and Guard Systems (latest edition) shall apply

Proposed ANS AWI SMA 0643 – October 2020 DRAFT FOR REVIEW ONLY - DO NOT DISTRIBUTE

WOOD SPECIES RAIL

Maximum Permitted Joints in Top Rail Per 15’-6” Length Ply of

Premium Custom Economy Alder, Red 1 1 S Anigre 1 1 S Ash, White 0 1 S Basswood 0 1 S Beech, American 0 1 S Beech, European 0 1 S Birch, Yellow - natural 0 0 S Birch, Yellow - select red 0 0 S Birch, Yellow - select white 0 0 S Cedar, Western Red 0 0 S Cherry, American Black 1 1 S Fir, Douglas - flat grain 0 0 S Fir, Douglas - vertical grain 0 0 S Hickory, True Group 1 1 S Mahogany, African - plain sawn 0 1 S Mahogany, African - quarter sawn 0 1 S Mahogany, American 0 0 S Makore 1 2 S Maple, Hard - natural 0 1 S Maple, Hard - select white 0 1 S Maple, Soft - natural 0 1 S Oak, English Brown 1 1 S Oak, Red - plain sawn 0 1 S Oak, Red - rift sawn 1 1 S Oak, Red - quarter sawn 1 1 S Oak, White - plain sawn 0 1 S Oak, White - rift sawn 1 2 S Oak, White - quarter sawn 1 2 S Pecan Group, Hickory 1 2 S Pine, Eastern or Northern White 0 1 S Pine, Ponderosa 0 1 S Pine, Southern Yellow 0 1 S Pine, Sugar 0 1 S Poplar, Yellow 0 1 S Redwood, flat grain heartwood 0 0 S Redwood, vert. grain heartwood 0 0 S Teak 0 1 S Jatoba S S S Sapele S S S Walnut, American Black 1 2 S *S - Requirements set forth in AWI/SMA 0643 - Wood Stair, Handrail, and Guard Systems (latest edition) shall apply

Proposed ANS AWI SMA 0643 – October 2020 DRAFT FOR REVIEW ONLY - DO NOT DISTRIBUTE

WOOD SPECIES TREAD Maximum Number of Staves Per 12” Depth

Premium Custom Economy Oak, Red - rift sawn 4 5 S Oak, Red - quarter sawn 4 5 S Oak, White - plain sawn S S S Oak, White - rift sawn 4 5 S Oak, White - quarter sawn 4 5 S Teak 4 5 S Walnut, American Black S 5 S *S - Requirements set forth in AWI/SMA 0643 - Wood Stair, Handrail, and Guard Systems (latest edition) shall apply

WOOD SPECIES RISER Number of Staves Per 7.75” Height

Premium Custom Economy Oak, English Brown 3 3 S Walnut, American Black 3 3 S *S - Requirements set forth in AWI/SMA 0643 - Wood Stair, Handrail, and Guard Systems (latest edition) shall apply