Creating U shaped winder stairs

[Doug_N]

None of the winders in the examples could be used in my jurisdiction, or, I suspect, anywhere in Canada.

Wok-cz example doesn't count because they are not winders, and would be allowed.

 

Here is the code for winders in stairs in Canada (using the Ontario Building Code version).

 

Here is what the code says about the narrow end of tapered stairs (as in winders).

 

Ontario Building Code - Volume 1, O. Reg. 332/12, Article 9.8.4.3. of Division B

9.8.4.3. Dimensions for Tapered Treads

(1) Except as provided in Sentence (2) and Articles 9.8.4.5. and 9.8.4.5A., tapered treads shall have a run that,

(a) is not less than 150 mm (5-7/8") at the narrow end of the tread, and

(b) complies with the dimensions for rectangular treads specified in Table 9.8.4.1. when measured at a point 300 mm (11-13/16")  from the centre line of the inside handrail.

(2) Tapered treads in required exit stairs shall conform to the requirements in Article 3.4.6.9.

(3) The depth of a tapered tread shall be not less than its run at any point and not more than its run at any point plus 25 mm .

 

Ontario Building Code - Volume 1, O. Reg. 332/12, Article 9.8.4.5. of Division B 
 9.8.4.5. Winders

A-9.8.4.5. Winders.
(1) Stairs within dwelling units are permitted to contain winders that converge
to a centre point provided,
(a) the winders turn through an angle of not more than 90°,
(b) individual treads turn through an angle of not less than 30° or not more
than 45°, and
(c) adjacent winders turn through the same angle.
(2) Where more than one set of winders described in Sentence (1) is provided in
a single stairway between adjacent floor levels, such winders shall be separated
in plan by at least 1 200 mm  (47 -1/4").

[Abdulhadi22]

On 2/6/2024 at 4:17 AM, Doug_N said:

None of the winders in the examples could be used in my jurisdiction, or, I suspect, anywhere in Canada.

Wok-cz example doesn't count because they are not winders, and would be allowed.

 

Here is the code for winders in stairs in Canada (using the Ontario Building Code version).

 

Here is what the code says about the narrow end of tapered stairs (as in winders).

 

Ontario Building Code - Volume 1, O. Reg. 332/12, Article 9.8.4.3. of Division B

9.8.4.3. Dimensions for Tapered Treads

(1) Except as provided in Sentence (2) and Articles 9.8.4.5. and 9.8.4.5A., tapered treads shall have a run that,

(a) is not less than 150 mm (5-7/8") at the narrow end of the tread, and

(b) complies with the dimensions for rectangular treads specified in Table 9.8.4.1. when measured at a point 300 mm (11-13/16")  from the centre line of the inside handrail.

(2) Tapered treads in required exit stairs shall conform to the requirements in Article 3.4.6.9.

(3) The depth of a tapered tread shall be not less than its run at any point and not more than its run at any point plus 25 mm .

 

Ontario Building Code - Volume 1, O. Reg. 332/12, Article 9.8.4.5. of Division B 
 9.8.4.5. Winders

A-9.8.4.5. Winders.
(1) Stairs within dwelling units are permitted to contain winders that converge
to a centre point provided,
(a) the winders turn through an angle of not more than 90°,
(b) individual treads turn through an angle of not less than 30° or not more
than 45°, and
(c) adjacent winders turn through the same angle.
(2) Where more than one set of winders described in Sentence (1) is provided in
a single stairway between adjacent floor levels, such winders shall be separated
in plan by at least 1 200 mm  (47 -1/4").

Something worthy