Flat Roofs Dominate Commercial Construction
The majority of commercial buildings in the Pacific Northwest use flat or low-slope roofing systems. Two systems dominate: TPO (Thermoplastic Polyolefin) and EPDM (Ethylene Propylene Diene Monomer). Both are excellent choices with distinct advantages.
TPO: Energy Efficient and Modern
TPO has rapidly become the most popular single-ply commercial roofing membrane. Its white reflective surface reduces cooling costs. Seams are heat-welded, creating a watertight bond stronger than the membrane itself.
- Highly reflective, reducing energy costs
- Heat-welded seams for superior waterproofing
- Resistant to UV, ozone, and chemical exposure
- Competitively priced with strong warranties
EPDM: Proven Durability
EPDM has been the workhorse of commercial roofing for decades. This synthetic rubber membrane is known for exceptional durability and flexibility across all temperatures.
- Proven 30-50 year track record
- Excellent flexibility in cold temperatures
- Low maintenance requirements
- Easy to repair if punctured
Which Lasts Longer?
EPDM has the edge in proven performance at 30-50 years. TPO is newer but expected to deliver 25-35 years. Quality of installation is the most critical factor for both.
Cost Comparison
EPDM typically costs less upfront. TPO costs slightly more but delivers energy savings that offset the difference over time, especially for buildings with significant cooling loads.
Our Recommendation
We recommend TPO for new construction where energy efficiency matters, and EPDM for budget-conscious projects. Expert installation is the key to long-term performance with either system.