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• N1102.6

  Maximum Fenestration

  • Even with trade-offs, average window U may not exceed 0.48 in zones 4-5 or 0.40 in 6-8, skylights 0.75 in 4-8, and SHGC 0.40 in zones 0-3; ICC 500 storm shelters are exempt.

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• N1110

  Additions

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• N1106

  Energy Rating Index Compliance Alternative

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• N1105

  Simulated Building Performance

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• N1111

  Alterations

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• N1102.5.1.3

  Maximum Air Leakage Rate

  Used in checks

  • Maximum tested leakage on the prescriptive path is 4.0 ACH50 in zones 0-2, 3.0 in 3-5 and 2.5 in 6-8; performance and ERI paths allow 4.0 ACH50 or 0.22 cfm/sq ft of envelope.

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• N1101.10.5

  Air-Impermeable Insulation

  • Insulation counts as air-impermeable at 0.004 cfm/sq ft or less at 75 Pa per ASTM E2178.

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• N1108.2.3

  Reduced Energy Use in Service Water-Heating Options

  • Water heating credits need the tabled UEF: gas storage 0.81 or 0.86, gas tankless 0.92 or 0.95, heat pump 2.20 to 3.75, solar SUEF 3.00 (electric backup) or 1.80 (gas).

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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.