The Ontario Building Code | Framing around Openings

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

(1) studs shall be doubled on each side of every opening where such openings="http://thehandyforce.com/windows/" title ="Window installer in Toronto">openings involve more than one stud space, and shall be tripled where the openings="http://thehandyforce.com/windows/" title ="Window installer in Toronto">openings in exterior walls exceed 2.4 m in width.

(2) studs described in Sentence (1) shall be fastened together by screws, crimping or welding to act as a single structural unit in resisting transverse loads.