EPDM vs TPO vs SPF vs Silicone Coating
Comparing the four flat-roof systems we install on Cape Cod — lifespan, cost, energy performance, and which one fits your building.
· Verified by Patrick Clifford, Co-Owner
Bottom lineEPDM (rubber) is the budget choice with 25-30 year life. TPO is a heat-welded white membrane — reflective, energy-efficient, 25-30 years. SPF (sprayed foam) is seamless and self-insulating — best for irregular roofs. GACO silicone coating restores an existing failing flat roof for ~50% of replacement cost with a 50-year warranty — our most-installed option for owners trying to avoid full replacement.
Side-by-side spec comparison
| Spec | EPDM Rubber | TPO | SPF (Sprayed Foam) | GACO Silicone Coating |
|---|---|---|---|---|
| Typical lifespan | 25–30 years | 25–30 years | 30+ years | 50-year warranty |
| Manufacturer warranty | 10–20 yrs | 15–25 yrs | 10–20 yrs | 50 yrs (15-yr labor) |
| Energy efficiency | Low (black/dark) | High (white reflective) | High (insulation built in) | High (white reflective) |
| Seams | Adhesive seams | Heat-welded (best) | Seamless monolithic | Seamless monolithic |
| Adds insulation R-value | No | No | Yes (~R-6/inch) | No |
| Works as a re-cover (no tear-off) | Sometimes | Sometimes | Often | Yes — ideal |
| Approximate cost / sq ft installed | $4.50–$8 | $5.50–$9 | $5–$10 | $3.50–$6.50 (vs $8+ replacement) |
| Best for | Budget residential & small commercial | Commercial, energy-conscious owners | Irregular roofs, cold-storage, high R-value needs | Existing failing flat roofs worth saving |
How to pick
- Your existing flat roof is failing but the deck is intact: get a free inspection — a GACO silicone coating will often save you 50% off the cost of replacement with a 50-year warranty.
- You're building new or fully tearing off: TPO is our most-recommended new flat-roof system for Cape Cod commercial. White, reflective, heat-welded seams, strong energy performance.
- Budget is tight and the roof is small: EPDM remains a workhorse — 25-30 years of service, low cost, easy to repair.
- Irregular shape, lots of penetrations, or you need insulation: SPF (sprayed foam) is the best fit — seamless and self-insulating.
All four are systems we are fully certified to install. We're also the first roofing company on Cape Cod certified in GACO-Flex silicone applications.
Free flat-roof inspection — including drone aerials
We'll walk you through which system fits your building and budget. No-pressure, written quote in 24-48 hours.