Single-Ply Membrane Roofing: TPO vs. EPDM Comparison

TPO (thermoplastic polyolefin) and EPDM (ethylene propylene diene monomer) are the two dominant single-ply membrane systems. Here's how they actually compare.

Heat Reflectivity

TPO: white surface reflects 80%+ of solar radiation — meets Energy Star requirements by default. EPDM: traditionally black/dark gray, absorbs heat. White EPDM available but less common and more expensive. Winner: TPO for reflectivity.

Seam Technology

TPO: heat-welded seams — when done properly, can be stronger than the membrane itself. EPDM: adhesive-tape or liquid adhesive seams — generally less reliable long-term than heat welds. Winner: TPO for seam integrity.

Cold Weather Performance

EPDM: excellent flexibility at low temperatures; long track record in northern climates. TPO: can become brittle in extreme cold, particularly older formulations. Winner: EPDM in harsh cold climates.

Cost

TPO (60-mil, fully adhered): $5.00–$8.00/sq ft. EPDM (60-mil, fully adhered): $5.50–$8.50/sq ft. Ballasted EPDM can be less expensive at $4.50–$7.00/sq ft. Generally comparable; EPDM is slightly more expensive fully adhered.

The Bottom Line

For most commercial applications: TPO is the better performing system due to superior seam technology and built-in reflectivity. EPDM has advantages in cold climates and has a longer performance track record. Both are solid choices for new construction and qualify for silicone coating restoration when they age.