Calculate spray foam insulation costs for your project. Estimate material, labor, and total expenses for open-cell and closed-cell foam by square foot.
Closed Cell
Higher R-value, acts as vapor barrier, more structural strength
Recommended Thickness for Application
2″ - 3.5″ for Exterior Walls
Closed cell provides vapor barrier and structural strength
You might also find these calculators useful
Planning a spray foam insulation project? Our calculator provides accurate cost estimates based on project area, foam type (open-cell vs closed-cell), thickness, application type, and installation method. Get detailed breakdowns of material costs, labor expenses, R-value performance, and energy savings to budget your insulation project effectively. Spray foam costs typically range from $1.00 to $4.50 per square foot installed, depending on foam type and thickness.
A spray foam insulation cost calculator estimates the total project cost by calculating board feet (area × thickness), material costs per board foot, and professional installation labor. It accounts for two foam types: open-cell ($0.44-$0.65/BF, R-3.5 per inch) and closed-cell ($1.00-$1.50/BF, R-6.5 per inch). The calculator provides cost breakdowns, R-value performance, and estimated energy savings to help homeowners evaluate ROI and compare against traditional insulation options.
Spray Foam Cost Formula
Total Cost = (Area × Thickness) × Material Cost/BF + Labor CostGet precise project costs based on industry-standard material pricing ($0.44-$1.50/board foot) and professional labor rates.
Evaluate cost differences between open-cell (lower cost, good sound dampening) and closed-cell (higher R-value, vapor barrier).
Receive recommended thickness ranges for attics (5-7″), walls (2-3.5″), crawl spaces, basements, metal buildings, and rim joists.
Calculate total R-value achieved based on foam type and thickness to ensure code compliance and energy efficiency.
Estimate annual energy savings (typically $1/sq ft/year) and payback period to evaluate investment ROI.
Compare material-only costs for DIY kits against full professional installation pricing.
Replace blown-in fiberglass or cellulose with spray foam for superior R-value and air sealing.
Insulate exterior walls during framing stage for maximum energy efficiency and code compliance.
Seal crawl space walls and rim joists with closed-cell foam to prevent moisture, mold, and pest issues.
Insulate basement walls and rim joists before finishing for moisture control and thermal comfort.
Prevent condensation and improve temperature control in pole barns, shops, and metal garages.
Seal rim joists in existing homes to eliminate drafts and reduce heat loss in a cost-effective project.
Calculate material costs for DIY foam kit projects under 600 board feet like small attics or basements.
Validate contractor quotes against calculated estimates to ensure fair pricing and avoid overcharges.
Open-cell spray foam costs $1.00-$2.00 per square foot installed at 3 inches thick. Closed-cell costs $1.50-$4.50 per square foot at 2-3 inches. Material-only (DIY) costs are 40-60% less. Prices vary by region, project size (larger = lower per sq ft), and thickness. Get 3+ quotes from licensed contractors for local pricing.
Open-cell ($0.44-$0.65/BF, R-3.5/inch, 0.5 lb density): Lower cost, excellent sound dampening, good for attics in mild climates. Not a vapor barrier. Closed-cell ($1.00-$1.50/BF, R-6.5/inch, 2.0 lb density): Higher R-value, acts as vapor barrier, adds structural strength, better for basements, crawl spaces, and walls. Choose based on moisture control needs, budget, and R-value requirements.
Attics: 5-7 inches open-cell or 3-4 inches closed-cell for R-30 to R-40. Walls: 2-3.5 inches closed-cell for R-13 to R-23. Crawl spaces/basements: 2-3 inches closed-cell for moisture control. Metal buildings: 1-2 inches closed-cell for condensation control. Rim joists: 2-3 inches closed-cell for air sealing. Check local building codes for minimum R-value requirements.
DIY spray foam kits (like Froth-Pak, Tiger Foam) are available for small projects under 600 board feet. Pros: Save 40-60% on labor. Cons: Learning curve, equipment rental, health/safety concerns (requires respirator, protective gear), limited warranty, potential for application mistakes. Professional installation recommended for whole-house projects (1,000+ sq ft) to ensure proper application, coverage, and code compliance.
Open-cell spray foam: R-3.5 to R-3.7 per inch. Closed-cell spray foam: R-6.0 to R-6.5 per inch. For comparison, fiberglass batts are R-3.7 per inch, cellulose is R-3.8 per inch. Closed-cell provides nearly double the R-value per inch, making it ideal for space-constrained applications like walls and rim joists.
Spray foam insulation lasts 80-100+ years with minimal degradation if properly installed. It doesn't settle, sag, or lose R-value over time like fiberglass or cellulose. The rigid structure and air-sealing properties remain effective indefinitely. Manufacturers typically offer 25-year to lifetime warranties. ROI through energy savings is typically achieved in 5-15 years depending on climate and energy costs.
Doubling thickness doubles board feet and material cost. Example: 1,000 sq ft at 2" = 167 board feet × $1.25/BF = $209 material. At 4" = 333 BF × $1.25/BF = $416 material (2× cost). Labor is based on area, not thickness, so impact is smaller on total installed cost. Each additional inch adds R-6.5 (closed-cell) or R-3.5 (open-cell) insulation value.
Typical energy savings: 20-50% on heating/cooling bills depending on climate, existing insulation, and home tightness. Average $1/sq ft/year in HVAC savings. A 2,000 sq ft attic project costing $4,000 might save $2,000/year, achieving payback in 2 years. Savings are highest in extreme climates (hot/cold), older homes with poor insulation, and when upgrading from no insulation. Use our calculator's estimate as a starting point.
Closed-cell spray foam acts as a vapor barrier (Class II, perm rating <1.0) preventing moisture intrusion, making it ideal for basements, crawl spaces, and rim joists. It's inorganic and doesn't support mold growth. Open-cell is NOT a vapor barrier (perm rating ~16) and requires separate vapor retarder in moisture-prone areas. Proper ventilation and addressing water sources remain essential—spray foam controls moisture migration but doesn't eliminate existing moisture issues.