How Much Does Blown-In Insulation Cost?
$0.90 – $2.40 / sq ft
National average: $900–$3,600 per attic
Estimate your cost
Adjust the options for a tailored ballpark — figures and the regional adjustment are approximate estimates. Always confirm with local quotes before you budget.
Blown-in (loose-fill) insulation is the fast, even way to insulate an attic floor — it’s blown in to any depth, flowing around joists and obstructions without cutting and fitting. It costs $0.90 to $2.40 per square foot installed in 2026, or about $900–$3,600 for a typical attic.
What you’re paying for
The cost is material plus the labor and blower to install it, with air sealing and any old-insulation removal as add-ons. Because it’s blown rather than hand-fitted, labor is efficient — one of the reasons it’s cheaper than batt or spray foam for covering an attic floor.
Cost by material
The three common materials differ in price and properties. The table below shows typical installed pricing per square foot.
Cellulose vs. fiberglass vs. mineral wool
Fiberglass is the cheapest and resists settling. Cellulose (recycled paper, treated for fire) packs slightly more R-value per inch and resists air movement well, but settles over time and shouldn’t get wet. Mineral wool is the premium option — fire- and moisture-resistant — at a higher price. For a dry attic, fiberglass and cellulose are both excellent value.
Top up, don’t always tear out
A money-saving truth: you can usually blow new insulation right over existing dry, undamaged attic insulation to boost R-value. Only remove the old stuff if it’s wet, moldy, or contaminated by pests — otherwise topping up is faster and cheaper.
How to save on blown-in insulation
- Top up over existing insulation instead of removing it when possible.
- Choose fiberglass or cellulose over premium mineral wool for attics.
- Air-seal first so the insulation actually performs.
- DIY with a rental blower for an accessible attic.
| Component | Typical range | Notes |
|---|---|---|
| Material + install | $0.90 – $2.40 / sq ft | — |
| Air sealing | $350 – $3,000 | — |
| Baffles / vent chutes | $100 – $500 | — |
| Old insulation removal | $1 – $1.50 / sq ft | — |
| Option | Typical range | Notes |
|---|---|---|
| Fiberglass | $0.90 – $2.00 / sq ft | — |
| Cellulose (recycled) | $1.00 – $2.40 / sq ft | Higher R per inch; eco-friendly |
| Mineral wool (Rockwool) | $1.50 – $3.00 / sq ft | Fire- and moisture-resistant |
What affects the price
- Material Fiberglass is cheapest; cellulose offers more R-value per inch; mineral wool is premium and fire-resistant.
- R-value / depth More inches to hit a higher R-value cost more.
- Attic vs. walls Blowing into open attic floors is cheap; dense-packing existing walls costs more.
- Air sealing Sealing gaps before blowing is essential for the insulation to work.
Frequently asked questions
- How much does blown-in insulation cost?
- It runs $0.90–$2.40 per square foot installed, or about $900–$3,600 for a typical attic, depending on material and depth.
- Cellulose vs. fiberglass blown-in — which is better?
- Fiberglass is cheapest and won't settle much; cellulose (recycled paper) has slightly higher R-value per inch and better air resistance but can settle and absorb moisture if wet. Both perform well in a dry attic.
- Can I blow insulation over existing insulation?
- Yes — adding blown-in over existing (dry, undamaged) attic insulation is a common, cost-effective way to boost R-value. Remove old insulation only if it's wet, moldy, or pest-damaged.
- Does blown-in insulation settle?
- Cellulose settles somewhat over time (installers account for it by adding extra depth); fiberglass settles less. Quality installs target the settled R-value.
- Can I DIY blown-in insulation?
- Yes — many home centers rent or lend a blower with bagged insulation. It's a feasible DIY for an accessible attic, though air sealing first still matters.
- Should I air-seal before blowing insulation?
- Absolutely. Sealing penetrations and gaps first ($350–$3,000 depending on the attic) prevents air leakage from undermining the new insulation.
How we estimate: ranges reflect typical U.S. pricing for materials and professional installation, compiled and cross-checked against the current (2026) industry sources listed below (see our data & methodology). Your actual cost depends on your location, project size, material grade, and local labor rates — always get multiple written quotes before you commit.
Sources
Cost ranges on this page were checked against current (2026) data from these industry sources: