Flashing and penetrations
Chimneys, vents, skylights, plumbing pipes, roof-to-wall transitions, and other penetrations need carefully sealed flashing details. When a seal dries out, lifts, cracks, or separates, water can work below the roofing surface even when the rest of the roof looks intact from the ground.
Wind and storm damage
Strong wind can loosen shingles, shift tiles, lift edges, or damage exposed flashing. Hail and driven rain can also expose weak points. After a storm, the first interior sign may be subtle, such as a new stain, a damp odor, or discoloration near a ceiling seam.
Worn materials
Roofing materials change over time. Shingles can lose coverage, sealants can crack, coatings can wear, and low-slope seams can open. A leak may be isolated, but repeated leaks in different areas can indicate that the roof system needs more than another small patch.
Drainage and roof details
On flat and low-slope roofs, water movement matters. Drains, scuppers, seams, edges, rooftop curbs, and areas around equipment all deserve close attention. On sloped roofs, valleys, pipe boots, ridge details, and transitions can become the path water takes into the structure.