Ventilation: The Leak That Is Not a Leak — Inspection Notes
What a real inspection covers on an asphalt shingle roof in Sherman Oaks, and what usually gets skipped.
A roof inspection is only as good as what gets looked at, and a lot of what gets called an inspection is a walk round the garden with a phone camera. This is what a real one covers on an asphalt shingle roof in Sherman Oaks.
What actually matters
A shingle roof is a water-shedding system, not a waterproof one. Every course relies on the course above it and on the underlayment beneath, so the covering and the layer under it fail together and have to be judged together. An inspection that does not account for that is looking at the wrong layer.
The detail that is usually left out
An inspection is only as good as what gets looked at, and photographs of specific defects are what let you get a second opinion without a second visit. The starter course and the drip edge are where cheap work shows first. A starter strip laid the wrong way round, or an eave with no metal under the first course, will wick water back into the fascia no matter how good the shingles above it are. Anything under half an hour on an average house has skipped something.
What is specific to Sherman Oaks
Summer is the problem here. Sherman Oaks sits inland at the foot of the mountains with nothing to moderate it, so a roof surface that reads ninety degrees at the coast is well past a hundred and fifty on Foothill by mid-afternoon, and it holds that heat for weeks. Everything on the roof expands into it and contracts again overnight, and that daily movement, not the peak temperature, is what opens laps and backs fasteners out. Much of Sherman Oaks went up between the 1950s and the 1970s, which usually means original decking, ventilation that was never sized for this much heat, and often a layer somebody roofed straight over rather than tearing off.
The full inspection list
- Granule loss across the field, and how much is sitting in the gutters
- Curling, cupping or cracking, particularly on the sun-facing slopes
- Nail placement and whether shingles have begun to back off the deck
- Sherman Oaks construction, and whether it is woven, closed-cut or metal-lined
- Flashing at every wall, chimney, skylight and pipe penetration
- Deck condition underfoot, checked by walking rather than by eye
- Attic ventilation, both intake at the eave and exhaust at the ridge
Common questions
How long should an inspection take?
Long enough to get on the roof and into the attic. Anything under half an hour on an average house has skipped something.
Should I expect photographs?
Yes, and of the specific defects rather than general views. Photographs are what let you get a second opinion without a second visit.
The honest summary
Shingle roofs rarely fail suddenly. They give years of warning through granule loss and edge curl, and the difference between a planned replacement and an emergency one is usually whether anybody was looking. In Sherman Oaks the thing to watch is attic temperature and intake ventilation, because a Sherman Oaks attic that cannot breathe cooks the underside of the roof as hard as the sun cooks the top.
Free inspection, drone photography where access is difficult, and a written estimate with deck repair priced per sheet. No obligation.
More on Shingle Roofing
- Storm-Lifted Tabs After a Sherman Oaks Event — Budget PlanningShingle Roofing
- Storm-Lifted Tabs After a Sherman Oaks Event — Homeowner ChecklistShingle Roofing
- What a Shingle Re-Roof Costs in Universal City — The Short AnswerShingle Roofing
- What a Shingle Re-Roof Costs in Los Angeles — Long-Term ViewShingle Roofing