The 17 Most Common Questions About Spray Foam Roofing
Whether you're considering spray foam for the first time or evaluating it against other systems, here are the 17 most common questions — answered directly.
1. What is spray foam roofing?
Spray polyurethane foam (SPF) is a two-component liquid system applied to existing roofing. The components react and expand into a rigid, closed-cell foam that adheres to the substrate. A protective topcoat is then applied over the foam.
2. How long does spray foam roofing last?
With proper maintenance and recoating, indefinitely. West Roofing has foam installations from 1979 still performing today.
3. How much does it cost?
Typically $4–$8 per square foot for foam plus coating, depending on thickness and roof conditions.
4. Does spray foam need a topcoat?
Yes — always. Unprotected foam degrades within days of UV exposure.
5. Can spray foam go over my existing roof?
In most cases, yes — over TPO, EPDM, metal, BUR, and modified bitumen systems that are in acceptable condition.
6. What warranty is available?
Most manufacturers offer 10, 15, or 20-year warranties. At the end of the warranty, a recoat renews coverage.
7. How is the warranty renewed?
Power wash, inspect, repair any issues, apply fresh topcoat at required thickness, receive new warranty.
8. Is spray foam slippery?
Smooth silicone topcoats can be slippery when wet. Granules or textured coatings are used in foot traffic areas.
9. How does foam compare to TPO cost?
Similar upfront, but foam's renewable warranty creates enormous lifecycle cost savings over TPO replacement cycles.
10. Can spray foam correct ponding water?
Yes — this is one of foam's unique capabilities. It can be applied at varying thicknesses to build slope and direct drainage.
11. Does foam add insulation?
Yes — R-6.5 per inch, the highest of any roofing insulation.
12. How long does installation take?
Days to weeks depending on roof size. Large projects can cover tens of thousands of square feet per day.
13. Is foam installation disruptive?
Minimal. No tear-off, relatively quiet, business operations typically continue normally.
14. What maintenance is required?
Semi-annual inspections, drain cleaning, prompt repair of mechanical damage, and recoating per the warranty schedule.
15. Can spray foam be used on unusual roof shapes?
Yes — it's one of foam's greatest advantages. It conforms to any shape, including domes, curved surfaces, and complex penetration fields.
16. Is spray foam environmentally friendly?
More so than replacement systems — no landfill waste from tear-off, and energy savings from improved insulation.
17. How do I know if my roof qualifies for foam restoration?
A professional inspection with core samples will determine moisture levels and membrane condition. Contact West Roofing Systems for a free assessment.