Roof Inspection, Repair, and Maintenance
What to look for
A systematic inspection starts at the ground with a roof plan sketch, then moves to eaves, valleys, penetrations, and ridges. Look for granule loss and bare spots, curling, cupping, clawing, fishmouths, ridging, and blisters. Distinguish a blister - a localized raised bubble from trapped moisture or gas - from a ridge, a long linear lift along a deck joint, and from a thermal split, a straight crack from movement. On single plies, check seam edges, ponding, wrinkles, punctures, and flashing terminations. On metal, check fastener back-out, corrosion at cut edges, and sealant failure.
Diagnosing leaks
Water travels along decking, insulation, and framing, so the visible stain is often far from the entry point. Trace uphill and toward the nearest penetration, valley, or wall. Condensation from poor ventilation mimics a leak: it appears on cold-deck undersides and in patterns, not at a single point. Hail damage shows soft-metal dents on vents and valleys, granule displacement, and fractures; test suspicious spots by feel and from a ladder, not by walking the field.
Repair practice
Match materials and slope; a patch must lap into the water path. Cut blisters out and patch rather than nailing them flat. Single-ply patches lap at least 6 in. with proper primer and sealant. Replace flashing rather than recaulking it repeatedly. Repair soft decking, not just the surface.
Maintenance
Schedule annual inspections plus post-storm checks, clear drains and gutters, trim overhanging branches, limit foot traffic, and use walk pads on membranes.
Traps
Questions that blame a distant ceiling stain on the nearest shingle, or that treat blistering as hail damage.