Flat Roof Repair
Flat roofs leak where the membrane cracks, blisters or opens at a seam, usually near spots where water pools. Professional flat roof repair typically costs $300–$1,100, or about $2.50–$10 per square foot of repaired area.
Last reviewed September 2026
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Does water pool on the roof?
After rain, note where water stands for more than two days. Leaks are usually at or just downhill of those spots.
Signs it's this problem
- Ceiling stains below the roof after rain
- Puddles that remain on the roof for more than a day or two
- Cracks, bubbles or lifted seams in the membrane
- Soft or spongy spots when walking on the roof
Why it happens
Water drains slowly from a flat roof, so any split, blister or open seam sits under standing water. Sun, foot traffic and clogged drains speed up the damage.
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Safety: Stay well back from roof edges without railings, and don't work on a wet membrane.
Flat Roof Repair cost
| Job | Typical cost |
|---|---|
| Typical flat roof repair | $300–$1,100 |
| Flat roof repair per square foot | $2.50–$10/sq ft |
| Larger repairs (insulation affected) | $1,100–$2,500 |
Got a quote? Check if it's fair
Typical professional price for this job: $300–$1,100
Common questions
Why does water pool on my flat roof?
Clogged drains, sagging decking or too little slope. Water that stays more than a couple of days shortens the membrane's life and should be corrected.
Can I patch a flat roof myself?
Small, clean punctures and seam lifts can be patched with a kit made for your membrane (EPDM, TPO, modified bitumen). Use the right kit; mismatched products don't bond.