How much clearance is required for wood framing where a masonry chimney passes through a roof opening?

How much clearance is required for wood framing where a masonry chimney passes through a roof opening?

• A. 2 inches
• B. 1/2 inch
• C. 1 inch
• D. 1 1/2 inch

Answer: (A)

When a masonry chimney penetrates a wood-framed roof, you must keep a safe gap between the chimney and any combustible framing to prevent heat from reaching wood and risking ignition. The minimum clearance for wood framing around a masonry chimney is two inches. This spacing helps guard against radiant heat and any potential embers, and it allows room for proper firestop and flashing around the chimney. If you see a smaller gap like a half-inch or an inch-and-a-half, that would not meet typical code requirements and could compromise safety. In practice, two inches is ensured by using appropriate noncombustible materials or a listed chase around the chimney where it passes through the roof.

When a masonry chimney penetrates a wood-framed roof, you must keep a safe gap between the chimney and any combustible framing to prevent heat from reaching wood and risking ignition. The minimum clearance for wood framing around a masonry chimney is two inches. This spacing helps guard against radiant heat and any potential embers, and it allows room for proper firestop and flashing around the chimney. If you see a smaller gap like a half-inch or an inch-and-a-half, that would not meet typical code requirements and could compromise safety. In practice, two inches is ensured by using appropriate noncombustible materials or a listed chase around the chimney where it passes through the roof.