Residential · IRC 2021 §R1001.5 / §R1001.6
Fireplace Firebox Dimensions
Masonry firebox section to scale: 20" minimum depth, throat 8" above the opening and 4" deep, with 8" walls including firebrick lining or 10" without.. Referenced to IRC 2021 §R1001.5 / §R1001.6.
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