Many flat roof leaks in Tempe come from the small flat sections people forget about: a patio cover, an added room, or a flat roof tied into the main house. The leak often starts where the flat roof meets a wall or the pitched roof, at a drain that cannot keep up, or at one bad seam. All Valley Roofing, based in Tempe, repairs flat roofs on homes and small shops and starts every job with a Free Roof Report so you know exactly where the water is getting in.
Why Tempe has so many small flat roofs
Tempe has a wide mix of roofs. Homes near downtown and ASU often have flat or foam roofs. South Tempe has more tile roofs. Many homes combine the two: tile over the main house, and a flat roof over an added room or patio.
That mix is where leaks like to start. Two roof types, often built at different times, meet at one joint.
Where these flat roofs leak
The joint with the main roof or wall
An added roof must join the old roof the right way. Flashing - thin metal that helps seal the joint - sits where the flat roof meets the wall or the pitched roof above it. When that flashing loosens or rusts, or the sealant dries out, water runs straight into the joint.
Drains and low spots
Water leaves a flat roof slowly. If a drain or scupper is blocked, or the roof has a low spot, water sits. Water that sits for a day or two can point to a roof issue, and it can wear down a weak membrane.
Seams
On TPO and modified bitumen roofs, most leaks come from one bad seam. When the rest of the membrane is sound, that part can be cut out and patched.
Roof openings
Vents, pipes, and any equipment on the roof are openings, and each one is a place for water to get in.
Worn foam coating
On a foam roof, the top coat wears out first, not the foam. A thin or chalky coat lets the sun reach the foam underneath.
Signs to watch from inside and out
- A ceiling stain in the added room, or near where it meets the house
- Water marks on the wall where the patio roof attaches
- Puddles on the flat roof a day or two after rain
- Cracks, blisters, or loose edges you can see from a second-story window
Do not walk on the roof after rain. Take photos from the ground or from inside instead.
Patch it or replace it?
One bad seam, a small hole, or one bad spot by a roof opening may only need a patch. The joint with the main roof may need new flashing and sealant.
Replacement starts to make sense when the membrane is dry and hard, many seams are bad, or water sits on a bad seam so a patch will not hold. On foam, soft or wet foam means more than a new coat. The report shows which you have. For the bigger picture on flat roof types, see TPO vs modified bitumen vs foam.
Planning an addition or a new patio roof?
If you are adding a room or covering a patio, call while the work is being planned. We want to see the old roof early so we can plan the joint, and we tell you who will get the permit before work starts. See new builds and remodels.
FAQ
Can you fix just the patio roof and not the main roof?
Yes. Many repairs are limited to the flat section or the joint. The report also notes anything on the main roof worth watching.
Do I need to be home?
No. The free roof check takes 45 to 90 minutes, and we can check the roof from outside.
What can change the cost of a flat roof repair?
Roof size, the number of drains and roof openings, and any bad wood found under the old roof. Your written quote shows the price.
Get the leak found
Request a Free Roof Report from All Valley Roofing. Learn more about flat and low-slope roofing, foam roofing, and our work in Tempe.
Next step: Free Roof Report
No cost. No obligation. Yours to keep. Tempe-based All Valley Roofing documents whether you need routine maintenance, localized repair, underlayment work, or a full system. Prefer a leak first? Go to roof repair.