Eighteen-Month-Old Shingle Roof With Reversed Drip Edge and Exposed Fasteners
An inspector is evaluating a 2,100-square-foot, 4:12 gable roof on a two-story house. The architectural asphalt shingles were installed 18 months ago, and the homeowner reports shingle tabs lifting along the rake and granules collecting in the gutters. From the eave, the inspector observes that the metal drip edge at the eave has its flange installed over the underlayment, while the rake drip edge flange is installed under the underlayment. The open valley uses metal flashing with shingles terminating about 3 inches from the valley centerline. Several field shingles show fasteners driven through the exposed nailing area, and one 1-inch nail head is visible through a tab. The roof deck is solid from the attic, and there are no active ceiling stains. The homeowner wants to know whether the roof is defective or simply showing normal wear.
1. Identify the installation details that are incorrect or at risk and explain the water path each could create.
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The eave and rake drip-edge details are reversed from typical practice. At the eave, the drip-edge flange should normally lie under the underlayment so water drains over the metal and away from the fascia; with the flange over the underlayment, water can get behind the metal and wick into the fascia or sheathing. At the rake, the drip edge is normally over the underlayment so wind-driven rain sheds over the metal; placing it under the underlayment can allow water to enter behind the rake trim. The exposed and overdriven fasteners are also defects: nails placed in exposed areas or driven too deep can puncture the shingle and create leak paths. The 3-inch valley setback is not automatically a defect; an open valley is acceptable if the metal is exposed and the shingles are trimmed neatly. The report should call out observed installation defects, not label the roof as normal wear.
2. The homeowner asks whether to repair or replace the roof. What should the inspector report, and what limitation applies?
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The inspector should not recommend full replacement based only on these visible conditions. The defects appear localized and correctable: the drip edge at the eave and rake may need to be re-laid in the proper sequence, and exposed or overdriven fasteners should be corrected by a qualified roofing contractor. The inspector should report the conditions factually, note that the roof is only 18 months old, and avoid determining warranty coverage. A key limitation is that the underlayment and concealed fastening are not fully visible, so the inspector cannot confirm whether hidden damage exists. The report should recommend evaluation and repair by a licensed roofing contractor and should not promise that correction of the visible details will eliminate all leakage risk.