Tapered Insulation: Worth the Money? — Signs to Watch
What you can check on a flat roof in the Valley from the ground, safely, in ten minutes.
You can learn a lot about a roof without going anywhere near it, and none of the checks worth doing require climbing. This is what to look at on a flat roof in the San Fernando Valley, safely, from the ground.
What you can check yourself
Flat roofs are not flat. They are built with fall, and the fall is what keeps them alive. Every other detail is secondary to whether water leaves the roof.
What to leave alone
Stay on the ground and use the attic. Binoculars from the driveway and a torch in the roof space find nearly everything worth finding. Drainage does not fail in the storm; it fails in the eight dry months beforehand. A drain that has been dry since April collects grit, leaves and debris, and nobody looks at it until water is coming through a ceiling. As soon as you find something you cannot explain, stop looking and get it assessed.
What is specific to the San Fernando Valley
Summer is the problem here. The Valley runs ten to fifteen degrees hotter than the coast and holds it for weeks, so a roof surface that reads 90 degrees in Santa Monica is well past 160 in Van Nuys by mid-afternoon. Everything on the roof expands into that heat and contracts again overnight, and it is that daily movement, not the peak temperature, that opens laps and backs fasteners out. Most of the housing went up between 1950 and 1975, which means original decking, undersized ventilation and at least one previous layer that somebody roofed straight over rather than tearing off.
What we look at on an inspection
- Fall across the roof, and any area holding water beyond forty-eight hours
- Drain and scupper clearance, including underneath every strainer
- Membrane condition across the whole field, not only at the edges
- Flashing at every penetration, curb and item of rooftop plant
- Parapet termination and counterflashing along the full perimeter
- Insulation moisture, established by probe rather than by eye
- Evidence and quality of previous patching
Common questions
Is it safe to get on my own roof?
Generally no, and it is worth being blunt about it. Falls are the most common serious injury in this trade, and walking on a roof can damage the covering.
What can I check from inside?
A great deal. The attic shows staining, daylight through the deck and ventilation problems long before anything appears on a ceiling.
The honest summary
Ponding, blocked drainage and failed penetration detail account for nearly every flat roof call we take. If a quote does not mention drainage, it is a quote to recreate the same problem in a new material. In the San Fernando Valley the thing to watch is attic temperature and intake ventilation, because a Valley 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.