EPDM Rubber Roofs for Philadelphia Rowhomes
EPDM is the black rubber sheet that has covered Philadelphia flat roofs for decades. It is forgiving, easy to repair, and priced below most alternatives, as long as the seams and edges are done right.
EPDM rubber roofing on a Philadelphia rowhome runs about $6 to $9 per square foot installed, according to 2026 local figures, making it one of the lower-cost flat roof membranes here. It is a single black sheet glued to the roof with taped seams, and it works best on flat roofs with few penetrations and good drainage.
Why EPDM Still Covers So Many Philadelphia Roofs
EPDM, ethylene propylene diene monomer, is a synthetic rubber sheet that stays flexible through hot summers and freezing winters. Large sheets mean few seams, and on a narrow rowhome roof the whole field can often be covered with one or two pieces.
The weak points are the same on every EPDM roof: seams, corners and anywhere the sheet turns up a wall. The field of the membrane rarely fails. The details do, which is where the installer's time should go.
What Sets the Price of an EPDM Roof
- Tear-off or recoverGoing over one sound layer costs less than stripping several.
- Insulation and slopeTapered board to stop ponding adds material.
- Membrane thicknessThicker sheets cost more and resist punctures better.
- Walls and penetrationsParapets, pipes and skylights add detail time.
- AccessHoisting rolls onto a three-story row takes setup.
Recent Philadelphia figures put rowhome EPDM roofs at $6 to $9 per square foot installed. Those are market planning ranges, not our quote.
Fully Adhered EPDM Installation
On a residential roof we fully adhere EPDM: the sheet is relaxed for a while so it lies flat, then bonded to a clean cover board or insulation with adhesive across its entire surface. A fully bonded sheet does not billow in wind, handles occasional foot traffic, and keeps any future puncture from spreading water under the whole roof. The adhesive needs dry conditions and temperatures in its working range, so installation days are planned around the forecast. Brands we install include Firestone, Carlisle and GenFlex.
EPDM Seam and Flashing Details
Modern EPDM seams are closed with factory-applied or field-applied seam tape rather than liquid glue, then covered with a strip at T-joints where three sheets meet. At walls and parapets the membrane turns up and is held by a termination bar, then covered by counterflashing or coping. Pipes get pre-molded rubber boots. Almost every EPDM leak we are called to traces to one of these details, not the sheet itself, so they get the most attention and a final inspection before we leave.
EPDM over Existing Modified Bitumen
Where a rowhome has a single layer of modified bitumen on a dry, sound deck, a new EPDM roof can sometimes go over it after the surface is cleaned, flattened and covered with a recovery board. That saves the tear-off cost, but only when the conditions are met. If a core cut shows two layers already, wet insulation, or soft decking, the roof has to come off first. We cut the core before quoting, so you know which job you are paying for.
Brands we install and service
Pricing a rubber roof for your rowhome?
Call and we measure it, core the old roof, and quote the right scope.
What We See on Philadelphia Roofs
With most of Philadelphia's housing stock made up of attached rowhouses, and about four in ten homes built before 1940, a typical EPDM job here is a narrow flat roof sitting over decades of earlier roofing. That history decides the scope. A roof with one old layer on a dry deck may take EPDM over a recovery board; a roof carrying several layers of tar and felt does not, and the tear-off becomes part of the price.
How an EPDM Roof Goes On
- 1
Measure and core
Area measured and a core cut to count layers.
- 2
Scope and price
Recover or tear-off, with the reason shown.
- 3
Prepare the deck
Old roofing removed or flattened, boards replaced.
- 4
Board and adhesive
Cover or tapered board fastened, adhesive applied.
- 5
Sheet, seams, flashing
Membrane laid, seams taped, walls terminated.
- 6
Inspect and clean up
Every seam and detail checked before we leave.
EPDM Roofing Questions
It absorbs more sun than a white roof. Added insulation under the membrane offsets much of that; if heat is the main concern, TPO is worth comparing.
Yes. A clean EPDM patch with primer and tape is one of the easier flat roof repairs, which is part of its appeal.
Not directly under foot traffic. A deck needs sleepers or pavers on protection pads so the membrane is not walked on.
Roll roofing is asphalt felt with granules and many nailed laps. EPDM is one flexible rubber sheet with a few taped seams.
Yes. The party-wall edge is sealed so water cannot move between the two roofs.
More Replacement & Installation Work in Philadelphia
From our guides: TPO, EPDM or Modified Bitumen for a Rowhome Roof?
Get a Rubber Roof With the Details Done Right
Call for a measured quote. We core the old roof first so the price matches the job.