| 9.8.9. |
Construction |
| 9.8.9.1. |
Loads on Stairs and Ramps
- Except as specified in Articles 9.8.9.4. and 9.8.9.5., stairs and ramps shall be designed for strength and rigidity under uniform loading criteria to support specified loads of
- 1.9 kPa for stairs and ramps serving not more than one dwelling unit or a house with a secondary suite including their common spaces, and
- 4.8 kPa for other stairs and ramps.
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| 9.8.9.2. |
Exterior Concrete Stairs
- Exterior concrete stairs with more than 2 risers and 2 treads shall be
- supported on unit masonry or concrete walls or piers not less than 150 mm in cross section, or
- cantilevered from the main foundation wall.
- Stairs described in Sentence (1), when cantilevered from the foundation wall, shall be constructed and installed in conformance with Subsection 9.8.10.
- The depth below ground level for foundations for exterior steps shall conform to the requirements in Section 9.12.
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| 9.8.9.3. |
Exterior Wood Steps
- Exterior wood steps shall not be in direct contact with the ground unless suitably treated with a wood preservative.
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| 9.8.9.4. |
Wooden Stair Stringers
- Wooden stair stringers shall
- have a minimum effective depth of 90 mm, measured perpendicularly to the bottom of the stringer at the point of minimum cross-section, and an overall depth of not less than 235 mm,
- be supported and secured top and bottom,
- be not less than 25 mm actual thickness if supported along their length and 38 mm actual thickness if unsupported along their length, and
- except as permitted in Sentence (2), be spaced not more than 900 mm o.c. in stairs serving not more than one dwelling unit or a house with a secondary suite including their common spaces, and 600 mm o.c. in other stairs.
- For stairs serving not more than one dwelling unit or a house with a secondary suite including their common spaces, where risers support the front portion of the tread, the space between stringers shall be not more than 1 200 mm.
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| 9.8.9.5. |
Treads
- Stair treads of lumber, plywood or O-2 grade OSB within dwelling units shall be not less than 25 mm actual thickness, except that if open risers are used and the distance between stringers exceeds 750 mm, the treads shall be not less than 38 mm actual thickness.
- Stair treads of plywood or OSB that are not continuously supported by the riser shall have their face grain or direction of face orientation at right angles to the stringers.
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| 9.8.9.6. |
Finish for Treads and Landings
- The finish for treads and landings of interior stairs in dwelling units, other than stairs to unfinished basements, shall consist of hardwood, vertical grain softwood, resilient flooring or other material providing equivalent performance.
- Treads and landings of interior and exterior stairs and ramps, other than those within dwelling units or within houses with a secondary suite including their common spaces, shall have a slip-resistant finish or be provided with slip-resistant strips that extend not more than 1 mm above the surface.
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