The Ontario Building Code | Framing around Openings

9.23.13.2. Framing around openings="http://thehandyforce.com/windows/" title ="Window installer in Toronto">openings

(1) Roof and ceiling framing members shall be doubled on each side of openings="http://thehandyforce.com/windows/" title ="Window installer in Toronto">openings greater than two rafter or joist spacings wide.