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• N1101.7

  Climate Zones

  • Use Figure or Table N1101.7 to find the climate zone by county; unlisted places use N1101.7.2. Moisture letters are A moist, B dry, C marine; an asterisk marks Warm Humid.

  Local review: San Antonio is in Bexar County, climate zone 2A and Warm Humid. Nearby counties differ (Kendall 3A, Medina 2B), so check the county for sites outside the city.

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• N1112

  Repairs

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• N1107

  Tropical Climate Region Compliance Path

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• N1103.3.3

  Ductwork Located Outside Conditioned Space

  • Ducts outside conditioned space are R-8 (3 in and larger) or R-6 (smaller); buried ducts meet this or a listed equivalent distribution efficiency.

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• N1102.3

  Radiant Barriers

  • Radiant barriers, where installed, follow ASTM C1743.

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• N1102.2.2

  Ceilings Without Attics

  • Ceilings without attic space may drop to R-30 where more won't fit, uncompressed over the plate, limited to 500 sq ft or 20 percent of ceiling area, whichever is less.

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• N1111

  Alterations

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• N1101

  General

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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.