Straight and Curved Runs in Stairs

(1)  Except as permitted in Sentence (2), stairs shall consist of,

    (a)   straight flights,

    (b)   curved flights, or

    (c)   spiral stairs.

    (2)  Stairs within houses and individual dwelling units may consist of,

    (a)   flights with rectangular treads and winders provided winders as described in Article are installed between floor levels, or

    (b)   flights with a mix of rectangular and tapered treads provided all tapered treads within a flight turn in the same direction.

    (3)  Curved flights in exits shall comply with Sentence

    (4)  Spiral stairs shall comply with Article

Article Ontario Regulation 332/12 Building Code,   O. Reg. 332/12: BUILDING CODE ( © Queen’s Printer for Ontario, 2021.