Spray foam insulation cost in Phoenix, AZ (as of October 2026)
Prices as of October 2026. Sources checked October 18, 2026.
Spray foam insulation in Phoenix costs $0.60 to $1.60 per board foot for open-cell foam and $1.30 to $3.10 per board foot for closed-cell foam, installed. Those are Angi's 2026 national ranges (updated September 9, 2026). We could not find a cost guide that publishes a measured Phoenix-only board-foot price, so the Phoenix attic and wall figures below are worked out from those rates, with the math shown.
A board foot is one square foot of foam one inch thick. Multiply the sprayed area by the thickness in inches and you have the board feet on a Phoenix spray foam quote. Most of the price swing comes from how thick the foam goes on, so thickness is the first number to check.
Phoenix spray foam price table
| Item | Open-cell | Closed-cell | Where the number comes from |
|---|---|---|---|
| Installed price per board foot | $0.60 to $1.60 | $1.30 to $3.10 | Angi, updated Sep 9, 2026 |
| Installed price per square foot of surface | $1.50 to $3.50 | $3.00 to $5.00 | HomeGuide, Dec 1, 2025 |
| R-value per inch (manufacturer label) | R-3.6 | R-6.8 to R-7.1 | Profoam product sheet |
| Inches needed for R-38 | 10.6 in | 5.4 to 5.6 in | R-38 divided by R per inch |
| 1,500 sq ft Phoenix roofline at typical thickness (6 in open, 3 in closed) | $5,400 to $14,400 | $5,850 to $13,950 | Derived, see method |
| 1,500 sq ft Phoenix roofline at R-38 | $9,500 to $25,300 | $10,400 to $26,000 | Derived, see method |
| 1,000 sq ft of 2x4 wall (3.5 in open, 2 in closed) | $2,100 to $5,600 | $2,600 to $6,200 | Derived, see method |
| Published national attic job totals | $1,100 to $9,000 (Angi); $3,000 to $8,000 (HomeGuide) | Cost guides, not Phoenix-specific | |
| Minimum job fee many sprayers charge | $1,000 to $2,000 or more | HomeGuide, Dec 1, 2025 | |
Sources: Angi, "How Much Does Spray Foam Insulation Cost? [2026 Data]" (updated Sep 9, 2026); HomeGuide, "How Much Does Spray Foam Insulation Cost? (2026)" (Dec 1, 2025); Profoam product price sheet (R-value per inch and typical thickness).
Why a Phoenix attic job lands above the national averages
Phoenix sits in climate zone 2B, the hot-dry zone of the energy code. The 2024 IECC sets R-38 as the prescriptive ceiling insulation level for zone 2, and the City of Phoenix adopted the 2024 IECC with amendments that leave that table alone. At R-3.6 per inch, open-cell foam needs about 10.6 inches to reach R-38. That is a lot of board feet, which is why a code-thickness roofline job in Phoenix prices well above the national attic averages in the cost guides.
Many Phoenix homeowners are quoted foam on the underside of the roof deck rather than on the attic floor. Sealing the roofline makes the attic part of the conditioned space, so the air handler and ductwork that sit up there stop baking in summer attic air. The catch is surface area. A sloped roof deck is larger than the floor below it: about 5% larger at a 4-in-12 pitch and about 12% larger at 6-in-12. Add the gable walls and a 1,500 sq ft house can mean more than 1,500 sq ft of spraying.
One foam supplier's product sheet lists average roofline thicknesses of 6 inches for open-cell and 3 inches for closed-cell. At the label R-values that works out to about R-21.6 and R-20 to R-21, well under R-38. If a Phoenix bid uses those thicknesses, ask how it meets the code path on your permit before you compare it with a thicker bid. Our quote checker runs that board-foot math on any bid you have in hand.
Sources: DOE/PNNL, Energy Savings Analysis: 2024 IECC for Residential Buildings (ceiling R-49 to R-38 in zones 2 and 3); 2024 IRC Table N1102.1.3 (IECC R402.1.3), as reproduced by UpCodes; City of Phoenix, Building Construction Codes; City of Phoenix, 2024 IECC amendments (PDF); Profoam product price sheet (R-value per inch and typical thickness).
Walls cost less per job
Wall cavities cap the thickness. A 2x4 wall holds 3.5 inches, so open-cell foam in a wall stays near R-12.6 no matter who sprays it. The 2024 IECC table lists R-13 cavity insulation, or R-10 continuous insulation, for wood-framed walls in zone 2, so a full 2x4 of R-3.6 open-cell lands just under the R-13 line; on new or permitted wall work, ask the installer which product or compliance path gets the wall to R-13. Closed-cell is often sprayed about 2 inches deep in walls. Per 1,000 sq ft of wall, that is 3,500 board feet of open-cell or 2,000 of closed-cell. Existing finished walls in older Phoenix homes are a different job, since the drywall or stucco has to be opened first.
Sources: 2024 IRC Table N1102.1.3 (IECC R402.1.3), as reproduced by UpCodes; Profoam product price sheet (R-value per inch and typical thickness).
Rebates and tax credits that change the Phoenix price
Your electric utility decides most of this. Phoenix is split between SRP and APS.
- SRP customers: the SRP Insulation Rebate pays up to 75% of professionally installed attic insulation, capped at $600, when an attic below R-19 is brought up to R-38. The work has to be done by a participating SRP contractor who is BPI-certified and licensed in Arizona, usually with air sealing. New construction, attic spaces over unconditioned areas and mobile homes are not eligible. If the job qualifies, the $600 cap is what applies on a $5,400 roofline job; SRP's page describes attic insulation, so confirm a roofline foam job with SRP at (602) 274-6808 before counting on it.
- APS customers: we found no general insulation rebate on aps.com. Arizona Corporation Commission Decision No. 81584, effective January 1, 2026, set the budget for APS's Existing Homes Program to $0 and kept the Low Income Weatherization budget in place, so income-qualified weatherization is still listed on APS's assistance page.
- Efficiency Arizona: the state program lists up to $1,600 for insulation, air sealing and ventilation for income-eligible households, and says new program guidelines apply.
- Federal 25C credit: gone for 2026 work. The IRS says the Energy Efficient Home Improvement Credit is not allowed for property placed in service after December 31, 2025.
Sources: SRP, Insulation Rebate; Arizona Corporation Commission, Decision No. 81584 (Docket E-01345A-23-0088); APS, Your Energy, Your Options; APS, Assistance Programs; Efficiency Arizona; IRS, Energy Efficient Home Improvement Credit.
Every Arizona area we cover is on our Arizona page, with the national picture on insulation rebates for 2026 and the city details on our Phoenix spray foam page.
How we got these ranges
No published cost guide we checked gives a measured Phoenix board-foot price, so we did not invent one. We took Angi's national installed per-board-foot ranges and multiplied them by board feet for a stated job. For the attic rows the job is 1,500 sq ft of sprayed surface. Thickness comes either from a supplier's typical roofline figures (6 inches open-cell, 3 inches closed-cell) or from the inches needed for R-38 at manufacturer label R-values.
- Open-cell, 6 in: 1,500 x 6 = 9,000 board feet. 9,000 x $0.60 = $5,400; 9,000 x $1.60 = $14,400.
- Closed-cell, 3 in: 1,500 x 3 = 4,500 board feet. 4,500 x $1.30 = $5,850; 4,500 x $3.10 = $13,950.
- Open-cell to R-38: 38 / 3.6 = 10.6 in. 1,500 x 10.56 = 15,833 board feet, so $9,500 to $25,333, shown rounded as $9,500 to $25,300.
- Closed-cell to R-38: 38 / 7.1 = 5.35 in and 38 / 6.8 = 5.59 in. That is 8,028 to 8,382 board feet. Low end 8,028 x $1.30 = $10,437; high end 8,382 x $3.10 = $25,985. Shown rounded as $10,400 to $26,000.
- Walls, per 1,000 sq ft: 3,500 x $0.60 to $1.60 = $2,100 to $5,600 open-cell; 2,000 x $1.30 to $3.10 = $2,600 to $6,200 closed-cell.
These are planning numbers, not quotes. Phoenix labor, access, roof pitch and old insulation removal all move a real bid. To see where real Phoenix numbers land, get quotes from local installers and run each one through the quote checker.
Phoenix spray foam cost FAQ
How much does spray foam cost per square foot in Phoenix?
HomeGuide puts installed spray foam at $1.50 to $3.50 per square foot for open-cell and $3.00 to $5.00 for closed-cell. Those are national figures; we found no Phoenix-only number.
How thick should spray foam be in a Phoenix attic?
R-38 is the 2024 IECC prescriptive ceiling level for zone 2, which covers Phoenix. That takes about 10.6 inches of open-cell at R-3.6 per inch, or about 5.4 to 5.6 inches of closed-cell.
Is there a rebate for spray foam in Phoenix?
SRP customers may get up to 75% back, capped at $600, for raising an attic below R-19 to R-38 with a participating contractor, if the job qualifies. We found no general insulation rebate for APS customers.
Can I still claim the federal tax credit for insulation in 2026?
No. The IRS says the 25C credit does not apply to property placed in service after December 31, 2025.