Flat roofs fail differently. They need to be treated differently.
TPO, EPDM, and modified bitumen for flat sections, additions, and commercial buildings.
A pitched roof sheds water. A flat roof holds it, and every decision about a low-slope system follows from that. The failure modes are not missing shingles — they are ponding that never dries, seams that have opened, and the flashing around every rooftop unit, drain and parapet that the membrane has to be married into.
Flat and low-slope sections are far more common on houses than people expect. Rear additions, porch and garage roofs, dormer tops and bay window caps in the older housing stock of Delaware County and Harrisburg are frequently low-slope, and they are usually the part of the roof that leaks first because they were treated as an afterthought when the main roof was done.
We install single-ply membrane — TPO, which is heat-welded and reflective, and EPDM, the black synthetic rubber that has been proving itself on commercial roofs for decades — along with modified bitumen where a torch-or-adhered multi-ply build-up is the better answer. Which one is right depends on the substrate, the drainage, and what sits on top of the roof.
Drainage comes before membrane, every time. If water is standing on a roof three days after it stopped raining, the answer is not a thicker membrane; it is tapered insulation, a re-pitched deck, or a drain that actually works. Membrane over a ponding problem buys a few years and no more.
What's included
- TPO, EPDM, and modified bitumen single-ply and multi-ply systems
- Heat-welded and correctly lapped seams — the usual point of failure
- Drainage assessed and corrected before any membrane goes down
- Flashing detailed at parapets, drains, curbs, and rooftop units
- Residential low-slope sections — additions, porches, dormers, bays
Where we do this work
We run 15 local offices across Pennsylvania, New Jersey and Maryland, and every one of them handles flat & low-slope roofing. Find the office nearest you:
Exton, PA · Allentown, PA · Lancaster, PA · Media, PA · Carlisle, PA · Doylestown, PA · Harrisburg, PA · Albrightsville, PA · Willow Grove, PA · Mt Laurel Township, NJ · Vineland, NJ · Williamstown, NJ · Hampton, NJ · Longport, NJ · Belcamp, MD
Not sure which office covers you? The service area index lists every county and town we cover. Or call (856) 292-7046 and we will route you.
Related services
Roof Installation · Roof Repair · Roof Replacement · Gutter Installation & Guards · Roof Inspection · Storm Damage Roof Repair
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Flat & Low-Slope Roofing — common questions
What is the difference between TPO and EPDM?
EPDM is a synthetic rubber membrane, usually black, with a very long track record; its seams are adhered or taped. TPO is a thermoplastic, usually white and reflective, and its seams are heat-welded into a continuous bond. TPO's reflectivity helps with cooling load; EPDM handles thermal cycling and ultraviolet exposure extremely well. The right choice depends on the building, not on which is "better".
Why does water pond on my flat roof?
Because the roof has insufficient slope, the deck has deflected, or a drain is blocked or badly positioned. Ponding that persists more than about two days after rain is a design or drainage problem, and no membrane will fix it permanently.
Can a flat roof be repaired, or does it need replacing?
Seam failures, punctures, and flashing detail failures are genuinely repairable. Widespread blistering, saturated insulation underneath, or a membrane that has gone brittle across the whole field means the system is finished.
How long does a flat roof last?
Longer than the reputation suggests, when it is detailed and drained properly. The systems that fail early almost always failed at a seam, a penetration, or a drainage problem that was present from day one.
Do I have a flat roof section without realising it?
Very possibly. Rear additions, porch roofs, garage roofs, dormer tops and bay window caps are frequently low-slope even on a house that reads as fully pitched from the street — and they are often the first part of a roof to leak.
Need flat & low-slope roofing? Get a free estimate today.
Free, no-obligation estimates. Licensed & insured in PA, NJ, MD & DE.