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The highest R-value per inch of any commercial insulation — and why it's the right choice for Southern California buildings, trucks, and marine applications.
Closed-cell spray foam is a two-part polyurethane that expands on application into a rigid, dense foam whose cells are fully encapsulated — no air pockets connecting to each other. That structure is what gives it three properties no other common insulation combines: R-6 to R-7 per inch (the highest per-inch R-value of any commercial insulation), a built-in vapor and moisture barrier, and enough rigidity to add measurable structural strength to walls, roofs, and panels.
By comparison, fiberglass batts run about R-3.2 per inch and do nothing to stop air movement — and air leakage is where most conditioned air is actually lost. Closed-cell foam insulates and air-seals in a single application.
Closed-cell foam is priced per board foot — one square foot at one inch thick — typically $1.00 to $2.00 per board foot. A common 3-inch application works out to $3.00 to $6.00 per square foot, with final pricing depending on total area, access, and prep.
It costs more up front than fiberglass, but the air-sealing typically cuts heating and cooling costs by 30–50%, and most owners see payback within 3 to 5 years. AAU Foam provides free on-site estimates so pricing is based on your actual building, not a guess.
Metal buildings and warehouses: foam bonds directly to metal panels, stops condensation drip, and stiffens the skin. Commercial roofing and walls: high R-value in limited depth. Truck bodies and refrigerated boxes: light, seamless, and moisture-proof. Fish holds and marine: closed cells won't absorb water. Residential attics, garages, and additions: maximum insulation where framing depth is limited.
Because it cures rigid and rejects moisture, closed-cell is the only foam type appropriate for marine work and exposed metal — which is exactly why it's the only product AAU Foam sprays.
The foam expands and cures within minutes of application. Most residential jobs are completed in a single day, and the space is typically safe to reoccupy within 24 hours. Larger commercial projects run 2–3 days depending on scope. Trained technicians follow all EPA and manufacturer safety guidelines during application.
R-6.0 to R-7.0 per inch — the highest R-value per inch of any commercial insulation. A 3-inch application delivers roughly R-19 to R-21 in a fraction of the depth fiberglass would need.
Typically $1.00–$2.00 per board foot (1 sq ft at 1 inch thick). A 3-inch application runs $3.00–$6.00 per square foot. AAU Foam provides free on-site estimates for exact pricing.
Closed-cell delivers about double the R-value per inch, acts as a moisture barrier, and adds rigidity — it's the right choice for metal buildings, trucks, marine applications, and anywhere moisture or space is a concern. Open-cell is cheaper per board foot but absorbs moisture and insulates less per inch.
Yes. Cured closed-cell foam is rigid and bonds to the substrate, measurably stiffening metal panels, truck bodies, and framed walls — one reason it's standard in transport and marine applications.
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