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| Roof covering | Minimum slope | Angle | Code |
|---|
| Asphalt shingles (double underlayment) | 2:12 | 9.46° | IRC R905.2.2 |
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| Asphalt shingles (single underlayment) | 4:12 | 18.43° | IRC R905.2.2 |
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| Metal roof shingles | 3:12 | 14.04° | IRC R905.4.1 |
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| Lapped metal panels, no sealant | 3:12 | 14.04° | IRC R905.10.1 |
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| Lapped metal panels with lap sealant | 0.5:12 | 2.39° | IRC R905.10.1 |
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| Standing seam metal | 0.25:12 | 1.19° | IRC R905.10.1 |
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| Clay and concrete tile | 2.5:12 | 11.77° | IRC R905.3.1 |
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| Slate | 4:12 | 18.43° | IRC R905.6.1 |
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| Wood shingles | 3:12 | 14.04° | IRC R905.7.1 |
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| Wood shakes | 4:12 | 18.43° | IRC R905.8.1 |
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| Mineral-surfaced roll roofing | 1:12 | 4.76° | IRC R905.5.1 |
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| Built-up roof | 0.25:12 | 1.19° | IRC R905.9.1 |
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| Modified bitumen | 0.25:12 | 1.19° | IRC R905.11.1 |
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| Thermoset single-ply (EPDM) | 0.25:12 | 1.19° | IRC R905.12.1 |
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| Thermoplastic single-ply (TPO, PVC) | 0.25:12 | 1.19° | IRC R905.13.1 |
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| Sprayed polyurethane foam | 0.25:12 | 1.19° | IRC R905.14.1 |
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| Liquid-applied coating | 0.25:12 | 1.19° | IRC R905.15.1 |
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| Photovoltaic shingles and modules | 2:12 | 9.46° | IRC R905.16.1 |
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