Tucson's monsoon runs June 15 through September 30. The first real storm of the season often arrives as a wall of dust followed by an hour of hard, wind-driven rain, exactly the combination that finds the weak spots on a roof. Most monsoon leaks trace back to a short list of causes, and most of those are visible from the ground or a ladder before the season starts. Here is what to look at, roof type by roof type, followed by a checklist.
What monsoon storms do to a roof
Wind lifts and shifts whatever is loose: tile, cap sheet edges, flashing, and anything mounted on the roof. Microbursts can bring winds of 50 to 60 mph or more in a narrow band, enough to slide tile and peel back a poorly adhered edge. Rain arrives faster than drains can take it, so any low spot or clogged scupper backs up and finds a seam. And the dust that precedes the rain clogs drains right before they are needed. Prep comes down to giving wind less to grab and water a clear way off the roof.
Tile roofs
Concrete and clay tile are the most common pitched roofing in the Tucson area, and the tile itself is tougher than it looks. The part that fails is underneath. The underlayment beneath the tile is the actual waterproofing, and it ages out. Depending on the product and how much heat it has absorbed, underlayment commonly lasts somewhere in the range of 20 to 30 years, sometimes less on hot south and west exposures, so a tile roof that looks fine from the street can be leaking underneath. Look for cracked, slipped, or missing tiles; debris in the valleys; exposed or brittle underlayment at the eaves; and bird nests under the first course. Avoid walking on tile to inspect it, since it cracks underfoot; binoculars do the job from the ground.
Flat and foam roofs
Flat roofs live and die by drainage. After a rain, note where water is still standing once the rest of the roof has dried; ponding stresses the membrane and finds any pinhole. Make sure every scupper and drain is clear and that overflow scuppers, if you have them, are not blocked or painted shut. Parapet walls deserve a close look: cracks in the stucco, failed caps, and open joints where the parapet meets the roof let wind-driven rain into the wall. Sprayed foam roofs are protected by an elastomeric coating that wears on a cycle; chalking, bare spots, blisters, cracks, and bird pecks mean the foam is exposed and a recoat is due. Recoat before the season, since the coating needs dry weather to cure.
Flashing and penetrations
Most leaks start at a transition, not in the open field of roofing. Check pipe jacks and vent boots for cracked rubber or sealant, look at skylight and HVAC curbs, and inspect where the roof meets a wall or chimney for lifted counterflashing. Satellite dishes, solar standoffs, and old antenna mounts are common culprits; anything screwed through the roof needs its seal checked yearly.
Gutters, scuppers, and drainage
Many Tucson homes have no gutters, which is fine as long as the ground slopes away from the foundation. Where you do have them, clear them and make sure downspouts discharge well away from the house, especially near doors and low windows. Where a roof drains onto a lower roof or a patio cover, look at that transition too.
Trees
Trim back anything that overhangs or can reach the roof when it bends in a gust. Mesquite and palo verde limbs are heavy and snap in wind; palm fronds clog scuppers. Remove dead limbs near the house.
Swamp coolers and rooftop HVAC
Evaporative coolers leak in their own ways. Check the stand and pan for rust, confirm the float valve shuts off and the overflow drains where it should, and inspect the roof jack and duct penetration for failed sealant. If you have a rooftop air conditioner, look at the curb flashing, the condensate drain line, and the service walk path, which is often where foam or coating is worn through.
After each storm
Look at the roof from the ground, scan ceilings and upper walls for new stains, and check the attic if it is safe to enter. Do not get on a wet roof or try to tarp during the storm; that is a job for after the wind dies down.
When to call a professional
Call if you have an active leak, can see daylight from the attic, notice sagging, cannot safely reach what needs checking, or have a tile roof old enough that the underlayment may be near the end of its life. Storm damage is often covered by homeowners insurance, depending on the policy, and prompt documentation helps. Skyline handles emergency tarp-ups and permanent roof repairs, the interior water damage a leak leaves behind, and the claim paperwork that goes with it. Storm-damage inspections are free.
The checklist
Before June 15
- Look over the roof from the ground with binoculars: cracked, slipped, or missing tile; debris in valleys; exposed underlayment.
- On flat roofs, clear every scupper and drain, confirm overflow scuppers are open, and note any ponding spots.
- Inspect parapet caps and stucco for cracks.
- Check every penetration: pipe jacks, vents, skylights, HVAC and cooler curbs, mounts.
- Check foam or coated roofs for chalking, bare spots, blisters, and bird damage; schedule a recoat if due.
- Clear gutters and downspouts; confirm grading slopes away from the house.
- Trim trees back from the roof and remove dead limbs.
- Service the swamp cooler: stand, pan, float, overflow, roof jack.
- Photograph the roof in good condition for your records.
After each storm
- Look at the roof from the ground for displaced tile or debris.
- Check ceilings and upper walls for new stains.
- Clear scuppers and drains again; dust storms refill them.
- Photograph any damage before it is repaired.
Related service: Roof and Exterior Repair — Storm-damage roof inspections are free; call or request a callback before the next storm rolls in.