Roof maintenance tips for rainy season in Van Nuys
Roof maintenance tips for rainy season in Van Nuys come down to timing: Van Nuys rain is concentrated, not spread through the year, so the pre-season pass matters more than any mid-winter reaction. This guide gives that pass, in the order a roofer would walk it.
Why rainy season hits Van Nuys roofs in bursts
Annual rainfall at Van Nuys Airport is 13.42 inches (NOAA 1991–2020), with February wettest at 3.79 inches and July at 0.00 inches. A single season can swing wildly: 29.76 inches in 2023–2024 against 6.05 inches in 2024–2025. The roof that survives a dry winter may fail in the first storm of a wet one, which is why maintenance is a pre-season job.
The dated benchmark is 4 February 2024, when 4.30 inches fell in one day. No maintenance pass can make a roof storm-proof, but a pass that clears valleys, checks flashing and confirms drainage removes the failures that turn an ordinary storm into an interior leak.
The pre-season maintenance pass
Clear valleys and gutters, and confirm downspouts actually discharge. Check flashing at chimneys, vents, skylights and walls, and check sealant for drying and gaps. Check ridge and cap for wind damage from the previous Santa Ana season, and check the attic for stains, damp insulation and daylight that were not there last season.
On tile roofs, check for displaced or cracked tile and, more importantly, for signs that underlayment beneath sound tile is ageing — that is the tile failure mode this site describes honestly. On flat roofs, check drainage, ponding areas, seams and parapet flashing before rain, not after.
Common pre-season mistakes
The most common mistake is cleaning only the gutters that are easy to reach and leaving the valleys blocked, since valleys carry the most water. Another is sealing over a flashing problem instead of repairing the flashing detail, which traps water until the next storm. A third is ignoring a small stain because it dried out: a stain that dries is still a record of an entry point.
If the pass finds soft deck, widespread staining, or a flat roof that ponds for days, the next step is a walked inspection and a written scope, not another season of patching. A permit is required — confirm the repair-vs-re-roof line with LADBS for your scope. Van Nuys is in the City of Los Angeles, so permits run through LADBS, not the County.
Related pages: roof maintenance and roof leak repair and Roofing in Van Nuys. To discuss your roof, see contact or call (818) 474-8963.
A few answers before you start
Before the winter rainy season, while the roof is dry and accessible, so valleys, flashing and drainage can be checked and repaired in order.
Valleys and drainage. Valleys carry the most water, and a blocked valley or failed downspout turns an ordinary storm into an interior leak.
No. Maintenance keeps small problems small. A roof at end of life, with widespread failure or a soft deck, needs a repair-versus-replacement decision in a written scope.
Schedule pre-season roof maintenance in Van Nuys
Call (818) 474-8963 to describe what you are seeing, or see contact for the address. Scope is discussed in writing before work starts.