When comparing flat roofing membranes, TPO (Thermoplastic Polyolefin) is significantly more energy-efficient than traditional EPDM due to its reflective properties and “cool roofing” design.

Key reasons for TPO’s superior energy efficiency include:

• High Reflectivity: TPO membranes are typically bright white and possess high Solar Reflectance Index (SRI) values. These surfaces reflect a large portion of solar radiation rather than absorbing it.
• Reduced Heat Absorption: Because the membrane bounces energy away, the building retains less heat. This leads to lower peak cooling demands and more stable indoor temperatures during warmer months.
• ENERGY STAR Qualification: Many TPO products earn ENERGY STAR ratings for their cooling performance, which helps reduce strain on HVAC equipment and lowers utility bills.

In contrast, traditional EPDM is a dark rubber membrane that historically absorbs more heat. While newer EPDM formulations can include reflective coatings to narrow this gap, standard TPO remains the industry leader for energy savings and mitigating the urban heat island effect.

• Flat Roof TPO vs EPDM: 2026 Comparison Guide