The Ontario Building Code | Spacing of Screws
184.108.40.206. Spacing of Screws
(3) Except as required by Sentence (4), for single-layer application on walls, screws shall be spaced,
(4) Except as permitted by Sentence (5), for single-layer application on walls, where gypsum board is required to provide bracing, lateral support or fire protection, screws shall be spaced not more than 300 mm o.c. on,
(b) top and bottom plates.
(5) Where a fire-resistance rating is determined based on Table 1 of MMAH Supplementary Standard SB-3, "Fire and Sound Resistance of building Assemblies", Sentence (4) need not apply for the purpose of fire protection.
(6) Screws shall be located not less than 10 mm from the side or edge of the board.
(7) Screws shall be driven so that the heads do not puncture the paper.