EPDM is a synthetic rubber roofing membrane, usually black, installed in large sheets and sealed with primer and seam tape. It stays flexible in cold weather and suits large, simple low-slope roofs and ballasted assemblies. When an existing EPDM roof is aging but still sound, a coating restoration can be an alternative to tearing it off.
Strong Contractors installs, replaces, repairs and restores EPDM roofing systems for commercial, industrial and institutional facilities. EPDM is a flexible synthetic rubber membrane designed for low-slope roofing applications and known for its resistance to weathering and temperature extremes. It is commonly selected for long service life, large sheet sizes and dependable performance across a wide range of climates.
Common Applications:
EPDM relies on clean substrates, compatible materials and disciplined execution at seams, perimeters and flashings. Strong coordinates the membrane, attachment system, adhesives, primers, seam tapes and accessories so each interface functions as part of one continuous assembly.
Most EPDM work starts with a decision about the roof already there: repair it, restore it, recover it or replace it.
| Spec | Typical Value |
|---|---|
| Membrane | EPDM (ethylene propylene diene monomer) synthetic rubber, single ply |
| Surface | Typical: black; white versions are available |
| Seams | Primed laps with seam tape, rolled |
| Attachment | Ballasted, mechanically attached or fully adhered |
| Sheet size | Large sheets that reduce the number of field seams |
| Thickness | Typical: 45 or 60 mil; 90 mil available |
| Manufacturer partners | Elevate, GenFlex, RPI and GAF |
| Warranty | No Dollar Limit (NDL) manufacturer warranties, typically 10 to 20 years depending on the system |
EPDM projects range from patching laps to a full tear-off. These factors set where yours lands.
Removing, reusing or disposing of stone and pavers is often a major line item on a ballasted EPDM roof.
Coating a sound membrane avoids tear-off and disposal. Replacement costs more but resets the insulation and lets the deck be inspected.
Fully adhered systems use more adhesive and labor. Ballasted and mechanically attached systems trade that for weight or fastener requirements.
Shrinkage at perimeters and curbs, and the number of penetrations, drive the amount of detail labor.
Cold-weather limits on adhesives and primers can affect schedule, staging and crew time.
| EPDM Roofing | TPO Roofing Systems | Silicone Roof Coatings | ||
|---|---|---|---|---|
| Surface | Black rubber | White thermoplastic | White seamless coating | |
| Seams | Taped laps | Heat-welded laps | Coats over existing laps | |
| Tear-off needed | Depends on existing roof | Depends on existing roof | No, on an eligible roof | |
| Heat gain | Higher | Lower | Lower | |
| Ballast | Can stay ballasted | Usually fastened or adhered | Can be reused over a protection mat | |
| Typical fit | Large, simple, cold-climate roofs | Reflective replacement or recover | Sound roof that needs more years | |
Often, if the membrane is still attached, the insulation is dry and the laps can be prepared. At the Douglas County Justice Center, Strong applied a liquid coating directly over the existing ballasted EPDM, added a protective mat for puncture resistance and reused the existing ballast instead of tearing the roof off.
Yes. Punctures, open laps and failed flashings on an EPDM roof can usually be repaired with compatible primers, tapes and patches. A repair only holds if the surrounding membrane is cleaned and primed correctly. Widespread lap failure or wet insulation usually means the roof needs a larger scope than spot repairs.
Neither wins everywhere. EPDM stays flexible in cold weather and works well on large, simple roofs and ballasted systems. TPO is white and reflective with welded seams, which helps where cooling cost matters. When a U.S. Space Force facility considered switching to black EPDM, Strong advised against it because of the added heat gain.
Aging EPDM can shrink, which pulls on perimeter flashings, corners and curbs. That tension can open laps or lift the membrane away from walls, and it is a common reason older EPDM roofs leak at the edges first. The fix depends on how far it has gone: reflashing, added securement or a larger scope.
The membrane is laid loose over the insulation and held down by river rock or concrete pavers instead of fasteners or adhesive. It installs quickly on large roofs, but the stone hides the membrane and has to be moved for repairs, inspections or replacement. Strong also offers ballast removal as a standalone service.
On many roofs, yes. Spray foam can go over existing EPDM with a cover board, adding insulation and a seamless surface without a full tear-off. The existing roof has to be checked for trapped moisture first, because wet insulation should never be sealed under a new system.
