Tropical Storm Isaias crossed the Philadelphia area on 4 August 2020. The National Weather Service's review counted eight confirmed tornadoes, including EF2 tornadoes in Philadelphia and Bucks County. The storm's lesson for roofs is that edges, ridges, flashing and gutters take the damage first.
Key takeaways
- The NWS review counted eight confirmed tornadoes from the storm, including EF2 tornadoes in Philadelphia and Bucks County.
- Tropical-storm-force gusts were widespread, and a few gusts reached hurricane force.
- Wind lifts shingles at the edges and ridges and tears flashing away from chimneys and vents.
- Tarping the opening comes first; the permanent repair follows the damage report.
- Photograph the damage before cleanup, for the insurer and for the roofer.
What did the storm do across the region?
The NWS Mount Holly review of 4 August 2020 lists eight confirmed tornadoes, including EF2 tornadoes in Philadelphia and Bucks County, with tropical-storm-force gusts across the region and a few at hurricane force.
A regional newspaper reported the Philadelphia-area tornado at 115 mph, on the ground for about 20 miles from Northeast Philadelphia to Doylestown. Early news counts of the tornadoes differed from the NWS's later count, so this guide uses the NWS figure.
The storm showed how far wind damage can reach across a dense city and its suburbs in one storm.
Which roof parts took the damage?
Wind damage after a storm like Isaias usually starts at the edges and ridges, where wind gets under the covering. Flashing at chimneys and vents and gutters are the next places that show damage.
On pitched roofs, the shingles at the edges, the ridge caps and the valleys are the first to lift. On flat roofs, the loose edges, the parapet flashing and the drain seams are the first to show damage.
A roofer checks those places first, then the rest of the roof, and documents the damage for the insurer.
| Roof part | What to look for | What it means |
|---|---|---|
| Shingle edges and ridge | Lifted, creased or missing shingles | Wind has got under the covering |
| Chimney and vent flashing | Bent or displaced metal | Water can enter at the penetration |
| Gutters and downspouts | Pulled from brackets or bent | Water is not carried away from the house |
| Flat roof parapet and drains | Displaced flashing or loose edge | Water can reach the wall or the ceiling below |
What should you do in the days after a storm?
Get temporary cover on any opening, photograph the damage before cleanup, and call a roofer to inspect. Keep receipts, and report the damage to your insurer promptly.
Temporary tarping stops further water getting in, and it is the first step the insurer will expect. Keep the receipts and the photographs together.
The permanent repair follows the inspection and the damage report. Do not pay in full or sign a completion certificate until the work is finished.
Frequently asked questions
Was Isaias the only storm that caused roof damage in the area?
No. This guide covers Isaias because the NWS has a detailed review of it. Other storms, including microbursts reported in the area, can also damage roofs.
How many tornadoes did the NWS count?
The NWS Mount Holly review counted eight confirmed tornadoes from the August 2020 storm, including EF2 tornadoes in Philadelphia and Bucks County.
What is the first thing to do after a storm opens my roof?
Get temporary cover on the opening if it is safe, photograph the damage and call (833) 751-2102. Tell your insurer promptly and keep the receipts.
Can wind damage show up weeks later?
Yes. Loose shingles, lifted flashing and gaps at a seam can let water in during the next rain. A roof walk after a storm finds the problems that are not yet leaking.
Sources
This guide is general information for Philadelphia County homeowners, not a substitute for an on-site inspection. Prices are estimates. See our disclaimer.