Combustibles stay 36 in from a masonry heater, with the space vented; with 8 in walls and 5 in channel walls the clearance drops to 4 in and 8 in to a combustible ceiling; listed heaters follow their listing.
With a fireclay liner in a single wythe, an offset may not push the upper flue centerline past the middle of the wall below, unless the offset is supported by masonry below; each corbel course still meets R1003.5.
Simple wall bracing works for up to three stories on concrete or masonry, walls 10 ft or less, roofs 15 ft eave-to-ridge, 130 mph or less in B or C, SDC A-C (A-B townhouses), with 1/2 in interior gypsum.
Searches all 4,276 IRC 2024 sections, 5,532 IBC 2024 sections and defined terms (Chapters 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33 so far) and each city's local rules as they are added. Section numbers and titles from the International Residential Code and International Building Code, 2024 editions, copyrighted by the International Code Council; the IRC's electrical chapters (34 to 43) follow NFPA 70, the National Electrical Code. Requirements are summarized in our words (IRC Chapters 3 to 43, IBC Chapters 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33); read the full text at the link on each result. Local values come from each city's published documents.
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