Flat roofs do their job quietly until they do not. Unlike sloped roofs where you might see a missing shingle from the ground, flat roof problems are often invisible until water shows up inside.
Regular inspection is the only way to catch issues early. Here is what to look for and what to do about it.
Signs of Trouble
Standing water more than 48 hours after rain is always a problem. Some ponding is normal immediately after rain. Persistent ponding means drainage is compromised. Water sitting on your roof accelerates deterioration and finds every weakness.
Blisters and bubbles in the membrane indicate moisture trapped underneath. Small blisters might be monitored. Large or growing blisters need attention. They can rupture and create direct paths for water entry.
Cracks and splits in the membrane surface expose underlayment to UV and water. Hairline cracks might be sealed with coating. Larger splits need patching or section replacement.
Separated seams are common in older roofs. The edges of membrane sections should be firmly bonded. Peeling or lifted edges need resealing before water gets underneath.
Soft spots when you walk on the roof suggest saturated insulation below. The membrane might look fine on top, but water is trapped in the layers underneath. This requires more extensive repair.
Damaged flashing around penetrations and edges often causes leaks attributed to the membrane itself. Check seals around pipes, drains, HVAC curbs, and wall junctions.
Prevention Is Cheaper Than Repair
Keep drains clear. Debris accumulates fast on flat roofs. A clogged drain turns normal rain into a ponding problem.
Trim overhanging vegetation. Leaves and branches that land on flat roofs hold moisture and can puncture membranes in wind.
Limit foot traffic. Every walk on a flat roof is wear on the membrane. Designate paths to rooftop equipment and install walk pads if traffic is frequent.
Schedule professional inspections at least yearly. A trained inspector catches what you miss and can address small problems before they grow.
Peak Builders maintains and repairs flat roofs throughout San Diego County. We help property owners extend roof life and avoid emergency situations.
