How Much Does Insulation Cost?

Insulation costs range from $0.30 to $3.50 per square foot depending on type and whether you DIY or hire a contractor. Here's a full breakdown for 2026.

2026 insulation cost by type

Type	DIY material cost	Installed (pro)	Best for
Blown-in fiberglass	$0.30–$0.50/sq ft	$0.80–$1.50/sq ft	Attic top-up
Blown-in cellulose	$0.25–$0.40/sq ft	$0.70–$1.20/sq ft	Attic, retrofit walls
Fiberglass batt (R-13)	$0.35–$0.60/sq ft	$0.90–$1.50/sq ft	Wall cavities
Fiberglass batt (R-19)	$0.45–$0.70/sq ft	$1.00–$1.70/sq ft	2×6 walls, floors
Mineral wool batt	$0.60–$1.00/sq ft	$1.20–$2.00/sq ft	Walls, soundproofing
Open-cell spray foam	N/A (not DIY)	$0.75–$1.50/sq ft	Walls, attic deck
Closed-cell spray foam	N/A (not DIY)	$1.50–$3.50/sq ft	Crawl spaces, rim joists
Rigid foam (EPS/XPS)	$0.25–$0.60/sq ft	$0.80–$1.50/sq ft	Continuous exterior, basement

Prices vary by region, installer, and job size. Get 3 quotes for large projects.

Full project cost estimates (2026)

Attic insulation (1,500 sq ft attic to R-49)

Approach	Total cost
DIY blown-in fiberglass	$500–$1,000
DIY blown-in cellulose	$400–$800
Professional blown-in	$1,500–$3,000
Professional spray foam (open-cell)	$3,000–$6,000

Wall insulation (1,200 sq ft of wall area, 2×4 framing)

Approach	Total cost
DIY fiberglass batt (new construction)	$500–$800
Professional batt (new construction)	$1,200–$2,000
Retrofit blown-in (existing walls)	$2,000–$4,000 professional

Crawl space insulation (1,000 sq ft)

Approach	Total cost
DIY fiberglass batt (floor)	$400–$700
Professional closed-cell spray foam (walls)	$2,500–$5,000

Is DIY insulation worth it?

Blown-in attic insulation is one of the few home improvement projects where DIY almost always makes sense:

Machine rental: Most stores offer free blower rental with purchase of insulation bags
Time: A 1,000 sq ft attic takes 4–6 hours with two people
Savings: DIY saves $800–$2,000 vs. professional installation on a typical attic

Wall and spray foam insulation are better left to pros due to precision requirements and equipment costs.

Energy savings payback

Project	Avg. annual savings	Payback (DIY)	Payback (pro)
Attic R-0 → R-49	$200–$500/yr	1–3 years	3–8 years
Attic R-19 → R-49	$100–$250/yr	2–5 years	5–12 years
Wall R-0 → R-13	$150–$350/yr	1–4 years	4–10 years

Based on national average natural gas and electricity costs. Savings are higher in colder climates.

Use the Insulation Calculator to estimate exactly how many bags you need and total material cost.

Frequently Asked Questions

How much does it cost to insulate a 1,500 sq ft attic?

Blown-in fiberglass DIY costs $400–$800 in materials for a 1,500 sq ft attic at R-38. Professional installation runs $1,200–$2,500 for the same job. Blown-in cellulose DIY is slightly cheaper: $300–$600 in materials.

Is spray foam insulation worth the cost?

Closed-cell spray foam costs $1.50–$3.50 per sq ft (material only) versus $0.30–$0.50 for blown-in fiberglass. The payback period is typically 5–10 years in energy savings. It makes sense in crawl spaces, rim joists, and areas where moisture control matters.

Can I install blown-in insulation myself?

Yes — most home improvement stores rent blowing machines for free with the purchase of bags. DIY blown-in is one of the highest-ROI home improvement projects: typical material cost for an attic is $300–$900, and energy savings often pay it back in 2–4 years.

How much does wall insulation cost?

For new construction, fiberglass batt wall insulation costs $0.50–$1.00 per sq ft installed (DIY materials only). Professional installation adds $0.60–$1.00/sq ft in labor. Retrofit wall insulation (blowing into existing walls) runs $1.50–$3.00/sq ft professionally installed.

Does insulation increase home value?

Properly insulated homes sell faster and for more in cold climates. The National Association of Realtors estimates attic insulation has an 80–100% cost recovery rate. Lower utility bills are a strong selling point in markets where heating costs are high.