Roofing in Lafayette, CA

Serving Lafayette and Surrounding Areas

Roof Problems Mill Valley Homeowners Actually Face

Coastal fog rolls off Mount Tamalpais most mornings and leaves roof surfaces damp until noon. Then winter storms arrive with wind-driven rain, and any gap opened by months of moisture becomes a leak.

Half of Mill Valley sits under redwood and oak canopy. These roofs fail from the top down, one shingle and one flashing detail at a time, never all at once.

• Granule loss on asphalt shingles. Fog and dew keep three-tab and architectural shingles damp through the morning, the mineral surface erodes, and UV light then reaches the asphalt. The mat curls and splits well before normal end-of-life wear.
• Failed step flashing and counter-flashing. Water wicks behind the metal where a roofline meets a chimney, dormer, or sidewall. Roof cement spread over the joint hides it for a season, and rot in the sheathing shows up two winters later.
• Clogged gutters and downspouts. Redwood needles pack the gutter trough, water backs up under the drip edge, and the eave, soffit, and fascia begin to decay. Windward rake edges take the same beating.
• Ice dams on shaded north slopes. Snow is rare here, but a cold snap after a wet storm backs water up behind the eave and under the starter course. Ice-and-water shield at the eave keeps it out of the attic.
• Wood shake and cedar shake at end-of-life. Decades of fog leave shakes split and soft, fasteners corrode, shake lifts, and the felt or tar paper underlayment usually fails first. An overlay over soft decking only hides the problem.
• Blocked soffit vents and a missing ridge vent. Warm, moist air traps against the roof deck, condensation forms on the plywood or OSB sheathing, and mold grows underneath while the shingles above cook from below.
• Sagging rooflines and deck rot. Soft sheathing lets rafters and trusses settle, nails pull through, and the ridge line sags. A roof inspection reads moisture content and deck condition before a repair turns into a tear-off.