The Ontario Building Code | Fastening
9.30.2.3. Fastening
(1) panel-type underlay shall be fastened to the subfloor with staples, annular grooved flooring="http://thehandyforce.com/flooring/" title ="Handyman flooring install Toronto">flooring nails or spiral nails, spaced not more than 150 mm o.c. along the edges and 200 mm o.c. both ways at other locations.
(2) Nails for panel-type underlay shall be not less than 19 mm long for 6 mm thick underlay and 22 mm long for 7.9 mm thick underlay.
(3) Staples for panel-type underlay shall,
(a) have not less than a 1.2 mm shank diameter or thickness with a 4.7 mm crown, and
(b) be not less than,
(i) 22 mm long for 6 mm underlay, and
(ii) 28 mm long for 7.9 mm and 9.5 mm underlay.
In Plain Language
Underlay must be fastened as set out in this article, ensuring it stays securely in place beneath the finish flooring.
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.