Spray foam insulation in Kennesaw, GA: get up to 3 quotes from vetted local installers
Request free quotes from up to three vetted spray foam installers serving Kennesaw and nearby Cobb County. Below: what your climate zone means for open vs closed cell, how much insulation to ask for, Georgia's energy code, and the rebates we could verify.
- Climate zone: 3A (2021 IECC)
- Attic target: R-49 (ENERGY STAR, uninsulated attic)
- State code: 2015 IECC with Georgia amendments (Georgia State Minimum Standard Energy Code)
- Utility rebates we verified: Georgia Power Home Energy Improvement Program
- Federal 25C credit: ended for 2026 installs
Facts last checked October 16, 2026. Sources are linked in each section.
Where we match quotes from this page
Requests from Kennesaw and ZIP codes whose center is within about 20 miles of it go to our Kennesaw, GA partner installers (13 ZIP codes): 30101, 30102, 30114, 30120, 30121, 30132, 30137, 30141, 30144, 30152, 30157, 30184, 30189. Outside these? Send the form anyway and we'll tell you if we can't match you.
Climate zone 3A: what it means for spray foam
Kennesaw's central point is in Cobb County, which the 2021 IECC county map assigns to climate zone 3A (mixed-humid in DOE's Building America terms). Zone 3A is a moist ("A") zone, which drives the vapor and R-value rules below.
Other counties within our Kennesaw service radius: Bartow County (3A), Cherokee County (3A), Paulding County (3A). All are zone 3A too.
Source: PNNL-33270, Guide to Determining Climate Zone by County (IECC 2021).
Open cell vs closed cell in Kennesaw, GA
Attic roofline: in climate zones 1–3 an unvented ("sealed") attic with open-cell foam sprayed under the roof deck is a common way to bring attic ductwork and air handlers inside the insulated envelope. The International Residential Code (Section R806.5) allows unvented attics with air-impermeable insulation such as spray foam; for a hybrid "flash-and-fill" assembly the foam layer at the deck must be at least R-5 in zone 3A.
Humidity: in a mixed-humid climate, a sealed attic becomes part of the conditioned house. Ask how the installer and your HVAC contractor will handle attic humidity (for example a small supply-air connection or dehumidification).
Closed cell earns its higher price where you need a vapor retarder or water resistance: crawlspace walls, rim joists, below-grade walls.
How much insulation to ask for
| Where | ENERGY STAR recommendation for zone 3A |
|---|---|
| Attic, uninsulated | R-49 |
| Attic with 3–4" of existing insulation | add R-38 |
| Floor over unconditioned crawlspace/basement | R-19 |
| Basement or crawlspace walls | R-5 continuous or R-13 cavity |
| Exterior walls (when re-siding) | add R-5 insulative wall sheathing beneath new siding |
To reach R-49 with foam alone you'd need roughly 13.2–14.0" of open cell (about R-3.5 to R-3.7 per inch) or 7.0–9.8" of closed cell (about R-5 to R-7 per inch). Many roofline spray foam jobs are installed thinner than that and justified through the code's performance path or the unvented-attic rules, so ask every installer to write the foam type, thickness and resulting R-value on the quote and explain how it meets your local code.
Source: ENERGY STAR, Recommended Home Insulation R-Values (based on 2021 IECC). ENERGY STAR's figures are recommendations for existing homes; your local code sets the legal minimum for new work.
Georgia energy code
2015 IECC with Georgia amendments (Georgia State Minimum Standard Energy Code). Georgia amendments set wood-frame wall insulation at R-13 in climate zones 3 and 4, and reduce ceiling insulation in zone 4 from R-49 to R-38.
Source: NAHB, "Residential Provisions of the IECC: State Adoption Status" (current as of May 2026); official state status at DOE Building Energy Codes Program.
Homes in Kennesaw, GA
Census figures for Kennesaw city (ACS 2020–2024 5-year estimates): about 14,380 housing units, a median year built of 1998, 11% built before 1980 and 14% built in 2010 or later. 58% are single-family detached homes and 3% are mobile/manufactured homes. 65% of occupied homes are owner-occupied, with a median owner-reported home value of $335,400.
- 67% of homes heat with utility gas. Spray foam makes a house much tighter, which changes how gas furnaces, water heaters and fireplaces draft, so ask whether the installer (or your HVAC contractor) will do combustion safety testing after the job. Some utility rebates require it.
Rebates and incentives for Kennesaw, GA
Utility programs that may apply, depending on which utility serves your address:
Georgia Power Home Energy Improvement Program
Attic insulation rebate of 50% of cost, up to $300 for electric customers ($200 gas), when existing attic insulation is below R-19 (per the 2026 program preconditions). Spray foam projects require a test-in and test-out, and homes with combustion appliances must pass combustion safety testing. Bundles with air and duct sealing pay more through affiliated installers.
Read on the program's own page October 16, 2026. Programs change; confirm before you sign.
Georgia state Home Energy Rebates
Limited, paused, or fully reserved Georgia's Home Energy Rebates
Electrification/appliance rebates (HEAR): "As of August 14, 2026, the HEAR program is paused and not accepting new applications. The HEAR program will be reopening with a limited amount of funding in October 2026."
Official source: Georgia Environmental Finance Authority (page says: As of August 14, 2026). Status text compiled via referencesource.org, last checked by them October 5, 2026. Full Georgia rebate page →
What spray foam costs (national published ranges)
We don't have enough local quotes for Kennesaw, GA to publish local prices, and we won't make them up. These national ranges are a starting point; your installers' quotes are what count.
| Example job (typical thickness) | Estimated installed range |
|---|---|
| 1,000 sq ft attic roofline, open cell (6") | $3,600–$9,600 |
| 1,000 sq ft attic roofline, closed cell (3") | $3,900–$9,300 |
| 1,500 sq ft walls, open cell (3.5") | $3,150–$8,400 |
| 1,500 sq ft walls, closed cell (2") | $3,900–$9,300 |
| 200 sq ft rim joists, closed cell (2") | $520–$1,240 |
Board feet × Angi's 2026 installed price per board foot. Angi reports a national average spray foam project of $2,888 (typical $1,455–$4,337). Check a quote you already have →
Questions to ask each installer
- Foam type, brand, thickness and resulting R-value for each area, in writing.
- Which climate zone and code edition they're designing to.
- Whether removal of old insulation, air sealing, and any required ignition/thermal barrier coating are included.
- Whether they participate in Georgia Power Home Energy Improvement Program, and who files the paperwork.
- Whether they'll do (or coordinate) combustion safety testing if you have gas appliances.
FAQ
What climate zone is Kennesaw, GA in?
Cobb County is IECC 2021 climate zone 3A, per PNNL's county list (PNNL-33270).
Should I use open-cell or closed-cell spray foam in Kennesaw, GA?
For attic rooflines in zone 3A, open cell is common and code-permitted in unvented attics; closed cell is worth the premium for crawlspace walls, rim joists and metal buildings.
How much attic insulation do homes in Kennesaw, GA need?
ENERGY STAR recommends R-49 for an uninsulated attic in zone 3A (or adding R-38 on top of 3–4 inches of existing insulation). Georgia's code: 2015 IECC with Georgia amendments (Georgia State Minimum Standard Energy Code).
Are there spray foam or insulation rebates in Kennesaw, GA in 2026?
The federal 25C tax credit does not apply to insulation installed after December 31, 2025. Utility programs that may apply, depending on which utility serves your address: Georgia Power Home Energy Improvement Program. Georgia's state Home Energy Rebate program status: Limited, paused, or fully reserved.
How much does spray foam cost in Kennesaw, GA?
We don't publish local prices until we have enough real local quotes. National published ranges are about $0.60–$1.60 per board foot for open cell and $1.30–$3.10 for closed cell, installed (Angi, 2026), and many companies have a $1,000–$2,000 minimum.
How does requesting quotes work?
Fill in the form once. We pass your request to up to three vetted partner installers who serve Kennesaw, GA, and they contact you to schedule an estimate. It's free and there's no obligation.
Other areas we serve in Georgia
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