The Ontario Building Code | Slope
9.8.5.4. Slope
(1) The slope of ramps shall be not more than,
(a) 1 in 10 for exterior ramps,
(b) 1 in 10 for interior ramps servingresidential occupancies,
(c) 1 in 6 for mercantileor industrial occupancies, and
(d) 1 in 8 for all other occupancies.