ANSI/AWI SMA 0643-2021 - Wood Stair, Handrail, and Guard Systems

5.0 Supplemental Information

5.1 Glossary

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 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)

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)

k) International Building Code (latest edition)

5.6 Exceptions to Material Requirements

a) The following 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 – ), Birch (Yellow – red), Birch (Yellow – select white), Cedar (Western Red), Cherry (American Black), Fir (Douglas – flat ), Fir (Douglas – ), 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 ), Redwood (vertical grain heartwood), Teak, Jatoba, Sapele, and Walnut (American Black).

WOOD SPECIES EXPOSED STRINGERS & S
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 – No exception is applicable. Requirements set forth in ANSI/AWI SMA 0643 – Wood Stair, , and Guard Systems (latest edition) shall apply

 

WOOD SPECIES EXPOSED S AND SKIRT BOARDS
Number of Linear Splices in Staves up to 14’ Minimum Length of Stave Where One-Piece Stave is Required
Premium Custom Economy
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 sawn 0 0 Unlimited 15’

 

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 – No exception is applicable. Requirements set forth in ANSI/AWI SMA 0643 – Wood Stair, Handrail, and Guard Systems (latest edition) shall apply

 

WOOD SPECIES
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 – No exception is applicable. Requirements set forth in ANSI/AWI SMA 0643 – Wood Stair, Handrail, and Guard Systems (latest edition) shall apply

 

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 – No exception is applicable. Requirements set forth in ANSI/AWI SMA 0643 – Wood Stair, Handrail, and Guard Systems (latest edition) shall apply

 

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 – No exception is applicable. Requirements set forth in ANSI/AWI SMA 0643 – Wood Stair, Handrail, and Guard Systems (latest edition) shall apply