The Ontario Building Code | Drips Beneath Window Sills
9.20.13.12. Drips Beneath window Sills
(1) Except for wall openings="http://thehandyforce.com/windows/" title ="Window installer in Toronto">openings located less than 150 mm above ground level, where a concealed flashing is not installed beneath window and door sills, such sills shall be provided with an outward slope and a drip located not less than 25 mm from the wall surface.
9.20.14. Protection During Work
In Plain Language
Drips (small grooves or projections) are required beneath window sills, as set out in this article, directing water to fall clear of the wall below rather than running down its face.
This is a plain-language summary of the 2012/2017 Ontario Building Code text above, for general understanding only and not a substitute for the Code. Always confirm current requirements against the 2024 edition (O.Reg. 163/24) or a qualified professional before construction.