Residential · IRC 2021 §R905.2.2

Asphalt Shingle Minimum Slope and Double Underlayment

Slopes drawn to scale: asphalt shingles only at 2:12 or greater, with double underlayment required from 2:12 up to 4:12, applied per R905.1.1.. Referenced to IRC 2021 §R905.2.2.

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