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2026 cost data

Insulation Cost in San Jose, CA (2026)

Insulation contractors in San Jose, CA price well above the national average. Here is what attic, wall, crawlspace and spray foam work should cost in the San Jose metro in 2026.

Insulation prices per square foot

Installed prices — material plus labor — adjusted for San Jose, CA labor rates.

Job typeInstalled cost / sq ft1,500 sq ft attic
Attic blown-in fiberglass (R-49)$2.63$3,940
Attic blown-in cellulose (R-49)$2.41$3,621
Attic fiberglass batts (R-38)$2.27$3,408
Wall batts, open framing (R-15)$2.48$3,728
Wall dense-pack retrofit (drill & fill)$3.69$5,538
Crawlspace floor or wall insulation$2.98$4,473
Basement rigid foam + framing$4.40$6,603
Open-cell spray foam (3.5")$2.77$4,153
Closed-cell spray foam (2")$5.11$7,668
Old insulation removal & disposal$2.20$3,302

What whole jobs cost

Typical projectLocal price range
Attic top-up (1,500 sq ft)$2,130 – $3,692
Full attic removal + re-insulate$4,544 – $7,668
Whole-house wall retrofit (2,000 sq ft home)$5,964 – $11,076
Crawlspace encapsulation + insulation$5,396 – $12,780
Garage conversion insulation$1,278 – $3,124
Whole-home spray foam (new build)$10,650 – $22,720

Climate zone 3 R-value targets

Department of Energy retrofit recommendations for this zone.

Attic
R-49
Walls
R-20
Floors
R-25
Check your current R-value →

Price your own job

These tables are averages. Punch in your real measurements for a number you can compare against a bid.

Insulation costAtticBlown-in bagsProject total

Statewide context

See how the San Jose metro compares with the rest of California.

Insulation cost in California →

Insulation cost FAQs for San Jose, CA

How much does attic insulation cost in San Jose, CA?

A 1,500 sq ft attic blown to R-49 runs about $3,349 to $4,729 installed in San Jose, CA, or roughly $2.63 per square foot. DIY with rented equipment cuts that by 45–60%.

Is insulation cheaper to DIY in San Jose, CA?

Yes. Labor is most of an insulation bid, so blowing your own attic or installing batts typically saves 45–60% of the installed price. Spray foam, dense-pack wall retrofits and removal jobs are worth hiring out.

What drives insulation prices in San Jose, CA?

Local labor rates, how far crews travel, attic access, whether old insulation has to be removed first, and the R-value your climate zone calls for. Material prices barely change between states — labor is the swing factor.

Are there rebates in San Jose, CA?

The federal 25C tax credit covers 30% of insulation and air-sealing material costs up to $1,200 per year, and most utilities add their own attic and air-sealing rebates. Always check with your utility before booking work.

Materials for an insulation job in San Jose, CA

Fiberglass Insulation Rolls R13Browse current prices and top-rated options on Amazon

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