The coating is the only part of a foam roof that touches the sun, and the only part that wears out. Choosing the right one — and the right thickness — is most of what separates a 25-year roof from a 12-year one.
| Acrylic elastomeric | Silicone | |
|---|---|---|
| Cost | Lower | Higher (material) |
| Ponding water | Softens and degrades under standing water | Tolerates ponding |
| UV life in Phoenix | 5–7 yrs typical | Longer; chalks less |
| Recoat later with | Acrylic or silicone (primed) | Silicone only |
| Dirt pickup | Lower | Higher (reflectivity drops faster; wash it) |
| Best for | Sloped foam roofs with good drainage; budget recoats | Low-slope roofs with ponding history; long-interval owners |
Coating is sold by dry mil thickness, not by "coats." Two passes to 20–30 dry mils is the Valley norm for a recoat; a thin single pass looks the same the day it's done and chalks through in two summers. Get the number in writing.
Durafoam reports a 15–35% drop in cooling costs after switching from tile or shingle to foam. Put in a summer bill and pick where you think your home lands.
Assumes cooling is ~60% of a Phoenix summer bill (APS and SRP both put summer cooling between half and two-thirds of usage). Savings vary with attic insulation, duct condition and the roof you're replacing. Recoating an existing foam roof restores reflectivity but does not add the full step-change.
Elastomeric and silicone coatings also go over modified bitumen, built-up and metal flat roofs as a restoration — often the cheapest way to get another 10 years. Identify your roof first: flat roof repair in Phoenix →
For foam roofs with decent slope, a quality acrylic elastomeric at 20–30 dry mils is the standard and the most recoatable. For roofs that pond, silicone. Both are white and reflective; both need the chalk test every spring.
Applied as a recoat, $2–$4 per sq ft (Travek) — $4,000–$8,000 on a typical home. Silicone sits at the top of that band or above.
Longer than acrylic in UV and far longer under ponding water; manufacturers quote 10–20 years. In practice the surface collects dust and loses reflectivity, so plan on washing it and re-testing every few years.
LAST REVIEWED 2026-11-01 · Prices on this site are published Valley rates and estimates, not a quote.