The wind does more than the water
Valley roofs are shallow, and a shallow roof is a large flat plane presented to a gust. What a monsoon storm does first is lift: at the eaves, along a rake, at the ridge. It only takes one edge breaking its seal or one tile shifting for the wind to have something to get underneath, and after that the rain has a path that did not exist an hour earlier.
That is why the open field of a roof is rarely where the failure is. The field is doing the easy job. The edges, the ridge and anything that sticks through the surface are doing the hard one.
Old penetrations are where it starts
Every hole in a roof was detailed by somebody, and on a lot of valley housing that somebody was working forty years ago. Post-war and 1970s stock in Mesa and Phoenix carries decades of patch repairs around evaporative cooler openings and the air-conditioning penetrations that came later, often stacked on top of each other.
Vent boots are the other reliable offender. The rubber collar around a plumbing vent perishes in this ultraviolet long before the roof covering above it wears out, and a cracked boot puts water directly into the roof structure with nothing visible from the ground at all.
What to look at after a storm, from the ground
Do not walk a hot tile roof, and do not walk a shingle roof in the afternoon. Almost everything worth spotting can be seen from a garden with a decent pair of eyes.
- A lifted, slipped or missing tile, particularly along an edge or the ridge
- Granules collecting where a downspout discharges, on a shingle roof
- Staining or dampness at the soffit and the eaves line
- A ceiling stain that appears a day after the storm rather than during it
- Anything that has come off the roof and landed in the garden
Why the stain that arrives late is the one to worry about
Water that shows up inside during the storm has taken a short route. Water that shows up a day later has been travelling — along a rafter, across the top of a ceiling, until it found somewhere to come through. The stain is telling you where it stopped, not where it started, and that is a roof to look at now rather than in October.
The same logic applies to a stain that is not growing. A dried mark is evidence of a path, and the path is still there waiting for the next storm.
We file the permit before anything comes off
A reroof is its own permit in most valley cities, and in Mesa, Phoenix and the rest that means a submittal and a review window. Starting a tear-off against a permit that has not cleared is how a house ends up open to the sky waiting on paperwork, and between June and September that is not a theoretical risk.
So the permit sits at the front of the programme rather than beside it, and the tear-off is scheduled against a weather window rather than against a diary.
After a storm, look at the edges and the penetrations rather than the middle, and treat a ceiling stain that arrives the next day as urgent rather than minor.
Questions we get asked
How do I tell whether a monsoon damaged my roof?
From the ground, and there is more to see than people expect: a lifted, slipped or missing tile along an edge or the ridge, granules collecting where a downspout discharges, staining at the soffit line, and anything that has come off the roof and landed in the garden. Do not walk a hot tile roof to check.
Why did my ceiling stain appear a day after the storm?
Because the water has been travelling — along a rafter or across the top of a ceiling — before it found somewhere to come through. The stain shows you where it stopped, not where it started. That is a roof to look at now rather than in October.
Where do Arizona roof leaks usually start?
Almost never in the open field of the roof. They start at the edges and the ridge, and around anything that penetrates the surface: old evaporative cooler openings, the air-conditioning penetrations that came later, and plumbing vent boots whose rubber has perished in the ultraviolet.
Do I need a permit to replace a roof in Phoenix or Mesa?
Yes. A reroof is its own permit in most valley cities, including Phoenix and Mesa, and it carries a review window. We file before anything comes off, because a tear-off started against a permit that has not cleared leaves a house open to the sky waiting on paperwork.
