Attached Patio Cover at 2:12 Slope Without a Permit
A homeowner in a suburb that has adopted the 2018 IRC wants a 14-foot by 22-foot attached patio cover. The plan: 2x6 rafters at 16 inches on center spanning 14 feet, a 2:12 slope, architectural asphalt shingles, a ledger bolted through brick veneer into the wall framing, and posts at the outer edge. The contractor proposes to 'skip the permit because it's an open patio cover' and to use one layer of 15-pound felt under the shingles. The existing house roof is 6:12. The patio cover will tie into the house wall below a second-story window and will cover a sliding door. There are no engineered drawings. The contractor says the old 2015 code allowed it. The homeowner wants to know if the shingles will leak at 2:12 and whether the inspector can make them tear it off.
1. Is a permit required, and which code edition governs? Can the contractor rely on the older 2015 code?
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The permit is required. An attached patio cover is a structure tied to the house and is not exempt simply because it is open. The applicable code is the edition adopted by the jurisdiction when the permit application is made, plus local amendments; a prior 2015 edition does not govern a new permit after the 2018 adoption. If the contractor builds without a permit, the inspector can require removal or exposure of concealed work, and the homeowner may face resale problems. The contractor should submit plans or a design, obtain the permit, and schedule inspections before covering framing and flashing.
2. Evaluate the proposed slope, underlayment, rafter sizing, and ledger attachment under the code.
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At 2:12, asphalt shingles are permitted only at or above the code minimum slope, but the underlayment must be double-layer because the slope is between 2:12 and 4:12. One layer of 15-pound felt is not enough. The 2x6 rafters at 16 inches on center spanning 14 feet are structurally inadequate; the span is far beyond a 2x6 rafter, so the design needs engineered sizing or a beam and column layout that shortens the span. Bolting a ledger through brick veneer is also improper because veneer is not the structural wall; the ledger must connect to framing or the cover must be self-supporting. Wall flashing, kick-out flashing, and roof-to-wall tie-in details must be shown.
3. What can the inspector require if the work is installed as proposed, and what should the homeowner do?
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The inspector can reject the work and require correction, including tear-off of the shingles if the underlayment or flashing is wrong. The contractor should not install shingles until the structural and flashing details are approved. The homeowner should get a written scope that includes permit, engineering, double underlayment, flashing, and inspection. If the contractor proceeds under the old code or without a permit, the homeowner should stop work and consult the local building department. The risk is not just leakage at 2:12; it is wind uplift, ledger failure, and water intrusion at the wall junction.