The Ontario Building Code | Starter Strip
9.26.7.2. Starter Strip
(1) A starter strip shall be installed along the lower edge of the roof so that it extends approximately 12 mm beyond the eaves and rake of the roof and fastened along the bottom edge with nails spaced not more than 300 mm o.c.
(2) Starter strips shall be,
(a) at least Type M mineral-surfaced roll roofing not less than 300 mm wide,
(b) shingles of the same weight and quality as those used as a roof covering with tabs facing up the roof slope, or
(c) pre-manufactured starter strips installed with sealant at the eaves.
(3) Starter strips need not be provided where eave protection of not less than Type M mineral-surfaced roll roofing is provided or self-sealing composite membranes consisting of polyethylene and bituminous material is provided.
In Plain Language
A starter strip is required along the eave before the first course of shingles, as set out in this article, providing proper support and sealing beneath the shingle tabs.
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.