QUALIFIED
INSTALLER
Minimum Non-Combustible Board
Dimensions
Minimum coverage area of non-combustible board.
Any wall fi nish applied to shaded area must be non-
combustible. We recommend extending the non-
combustible board well beyond the size shown to
avoid cracking due to diff erential shrinkage
— see page 40.
Non-combustible
board required
thickness:
1/2 inch (13 mm)
28
Framing Requirements
Min. 45-1/2" (1156 mm)