EPDM rubber roofing

What EPDM is and where it fits

EPDM (ethylene propylene diene monomer) is a synthetic rubber membrane. It comes in large sheets, so a roof has fewer seams than other systems. The sheets are fully adhered, mechanically fastened or held down with ballast, and the seams are joined with primer and seam tape rather than heat.

It fits low-slope offices, warehouses, industrial buildings and schools, and it's a common choice when an existing EPDM roof is being repaired or extended. Because rubber stretches and recovers, it handles building movement and big temperature swings well.

Pros and trade-offs

EPDM's strengths are durability and simplicity. Its main trade-off in Texas is heat:

• Stays flexible for decades, in summer heat and winter cold snaps
• Rubber absorbs hail impacts well, especially thicker sheets over a firm cover board
• Large sheets mean fewer seams, and repairs are straightforward
• Standard EPDM is black, so it absorbs heat: in DFW that adds to cooling load unless the building is well insulated
• White EPDM exists and reflects heat, at a higher price
• Seams are taped, not welded, so seam work is the detail that most needs skilled hands and regular inspection
• Oils, grease and some solvents damage rubber, so it's not for restaurant roofs

What's included in an EPDM roof

A complete EPDM scope from us covers:

• Tear-off, or a recover over a dry, single-layer existing roof where code allows
• Insulation sized for the energy code, tapered to drains where water ponds
• A cover board for a firm, hail-resistant base
• Membrane thickness options, typically 60 or 90 mil, priced as alternates
• Fully adhered or mechanically fastened attachment for the deck and wind exposure
• Flashing at walls, curbs and penetrations, with new termination bars, edge metal and drains

Lifespan and warranty

EPDM has one of the longest track records in commercial roofing. Roofs commonly last 20 to 30 years, and well-maintained ones go longer. The membrane itself usually outlives its seams and flashings, which is why inspections matter.

Our own workmanship on commercial roofs is covered by a 20-year workmanship warranty, in writing. The manufacturer's warranty on the materials is separate, and we register it for you at closeout.

Manufacturer material and system warranties are available. What applies depends on the manufacturer's requirements, and we explain your options in the proposal.

EPDM repair and maintenance

Most EPDM leaks come from seams that have let go, flashings that have pulled away from walls as the membrane shrinks with age, and punctures. All of these are repairable with the right primer, tape and patches. General-purpose sealants and asphalt products are not, and they make a proper repair harder later.

When an older EPDM roof is still dry underneath, a coating system or a recover can extend its life. We check the insulation's condition before recommending either.