Attic Insulation Cost Calculator
Attic Insulation costs $1,100 to $1,675 for a typical 1,000 sq ft job in 2026, against a national benchmark of $1,350. Labor runs 9.5 crew hours at $39.00 an hour. Enter a ZIP code to apply that area's measured wages for this work and its regional price level.
What makes up the price
Cost by size
National averages, before any local adjustment. Computed from the same model as the calculator above, so the two always agree.
| Area to insulate | Sq ft | Typical | Range |
|---|---|---|---|
| 550 sq ft | 550 | $825 | $675 to $1,025 |
| 800 sq ft | 800 | $1,125 | $925 to $1,400 |
| 1,000 sq ft | 1,000 | $1,350 | $1,100 to $1,675 |
| 1,350 sq ft | 1,350 | $1,750 | $1,450 to $2,175 |
| 1,700 sq ft | 1,700 | $2,150 | $1,775 to $2,675 |
Air seal first, insulate second
The most useful thing on this page, and the thing a quote for blown insulation almost never includes.
Insulation slows heat moving through a surface. It does nothing about air moving through a hole. A typical attic has dozens of holes in the ceiling plane: gaps around top plates, every wire and pipe penetration, the chimney chase, bath fan housings, recessed can lights, and the attic hatch itself. Warm air goes up through them in winter carrying moisture with it, and the insulation above does not stop it — loose fill is air-permeable by design.
The order matters because the holes are underneath. Seal them first with caulk, canned foam and sheet metal where there is heat, then blow the insulation over the top. Doing it the other way round means somebody raking 14 inches of cellulose aside to find the holes again.
Air sealing an attic runs $200 to $1,500 depending on how much of it there is. It is the best value in the whole of home energy work and it is usually sold separately, so ask for it by name:
- "Will you air seal the ceiling plane before insulating, and what is that priced at?"
If a contractor does not offer it, that tells you something about the contractor.
While the hatch is open: that hatch is the biggest single hole in the ceiling. Weatherstrip it and build a box of rigid foam over it, or buy a hatch tent. An hour's work, and in an unsealed attic it is worth more than the last four inches of depth.
What it costs
| 1,000 sq ft attic to R-49 | Per sq ft | |
|---|---|---|
| Topping up over existing | $1,350 | $1.35 |
| From bare joists | $1,875 | $1.88 |
| After removing the old material | $3,000 | $3.00 |
By material, from bare joists:
| Material | 1,000 sq ft | Per sq ft |
|---|---|---|
| Blown fiberglass | $1,750 | $1.75 |
| Blown cellulose | $1,875 | $1.88 |
| Fiberglass batts | $2,425 | $2.42 |
Spray foam is not in that table on purpose. It is sold by the board foot at a depth rather than to an R-value over an area — 5.5 inches of open cell is about R-20 and 2.5 inches of closed cell about R-17 — so comparing it against an R-49 figure compares two different things. Roughly, it runs $3.90 a square foot for open cell at that depth and $5.30 for closed cell, and it belongs on a roof deck or a crawl space wall rather than on an attic floor.
Measure the ceiling below, not the roof: a 1,500 square foot single-story house has about a 1,500 square foot attic, and the same house over two floors has about 750.
The old insulation usually stays
Removal is $1 to $2 a square foot, which on a 1,000 square foot attic is more than the installation that follows it. It takes this job from $1,875 to $3,000.
Dry, uncontaminated insulation does not need removing. Loose fill goes straight over the top of it and you pay only for the balance of the depth — which is why topping up at $1,350 is the cheapest route to code there is.
Three reasons it genuinely has to come out:
- Rodents have been living in it. Nesting, droppings and urine, and it does not improve under new material.
- It is wet, or has been. Matted, discolored, or showing a stain under a roof leak. Wet insulation does not insulate and whatever wet it needs fixing first.
- It is vermiculite. See below. This is the one that matters.
If a quote includes removal and none of those three apply, ask why.
If it looks like vermiculite, stop
Vermiculite is a loose fill that looks like small gray-brown or gold pebbles or accordion-like flakes, poured rather than blown, and common in houses insulated between the 1920s and the 1990s.
Most US vermiculite came from a mine in Libby, Montana that was contaminated with asbestos. The EPA's advice is to assume it contains asbestos and leave it alone unless it is tested.
So:
- Do not disturb it, and do not let anybody blow insulation over it without a conversation first — that puts a crew in an attic stirring it up.
- Have it sampled by an accredited lab, not by the insulation contractor.
- If it is positive, removal is asbestos abatement: a licensed abatement contractor, containment, and a cost that has nothing to do with the figures on this page.
Insulating over undisturbed vermiculite is sometimes the recommended course precisely because removal is so disruptive. That is a decision to make with a test result in hand.
Keep the eaves breathing
A roof needs air moving from the soffit vents up to the ridge. Loose fill blown into an attic will happily bury the soffit vents, and that is a real failure, not a cosmetic one — a roof that cannot breathe gets condensation on the underside of the deck in winter and is a common cause of ice dams in a house that has just been insulated.
The fix is a baffle at every rafter bay, a plastic or foam chute stapled between the rafters to hold the insulation back and keep a channel open. They are a couple of dollars each and are in the price here.
Ask: "Are you fitting baffles at every eave?" You can check afterwards from the ground — the soffit vents should still be visible as vents.
Depth, and why it barely matters to the price
| Target | 1,000 sq ft, bare joists | |
|---|---|---|
| R-30 | $1,600 | −15% |
| R-38 | $1,750 | −7% |
| R-49 | $1,875 | code minimum in most of the US |
| R-60 | $2,050 | +10% |
R-49 is the code minimum for an attic across most of the country, R-38 is enough in the warm South and R-60 is worth having in the far North.
The useful observation is how flat that table is. Depth scales the material and barely touches the labor — the truck, the hose and the crew are the same for ten inches as for sixteen — so going from R-49 to R-60 costs 10% on a job where the first inch cost hundreds. If you are in a cold climate and the hose is already in the attic, say yes.
Ask for a depth ruler stapled to a truss so you can see afterwards what you got. Any decent crew does this unprompted; settled loose fill is the oldest way to come up short.
What the money actually buys
Honest arithmetic, without a tax credit to hide behind.
Heating and cooling is roughly half of a typical household's energy bill, call it $700 to $900 a year. Taking a poor attic to R-49 saves perhaps 10 to 15% of that in a mixed climate, so $85 to $130 a year against a $1,350 job: a ten to fifteen year payback.
In a cold climate with an attic at R-11 and expensive fuel, the saving can be $250 to $350 a year and the payback four to six years. In Florida over a bare ceiling, likewise good. In a mild climate over an attic that already has R-30, the money is better spent elsewhere.
The federal tax credit is gone. Section 25C — 30% of the cost of insulation and air sealing — was repealed for anything placed in service after 31 December 2025. Most pages about attic insulation still advertise it; it does not apply to work done now. What does still exist:
- Utility rebates, which are often substantial and are usually administered per-project with paperwork the contractor files. Ask your utility before booking.
- State and local programs, which vary enormously.
- Income-qualified weatherization assistance, which in some states covers the whole job.
And the part that does not show up as money: an attic at R-49 with a sealed ceiling plane is a house where the upstairs rooms are the same temperature as the downstairs ones and the furnace cycles less. That is usually what people actually notice.
What you are paying for
Topping up a 1,000 square foot attic with blown cellulose to R-49, at $1,350 — or $1,875 starting from bare joists, which is what this breakdown shows:
| Labor, about 9.5 hours | around $519 |
| Cellulose, 1,000 sq ft at R-49 | $600 |
| Baffles, dams, netting and masking | $150 |
| The crew, the truck and the blower | $120 |
| Overhead and margin | the balance |
The hour and a half before any material moves is parking the truck where the hose will reach, masking the route through the house, fitting baffles at every eave, building a dam around the hatch and around any recessed can that is not rated for contact, and stapling up the depth ruler. Then two people for about four hours.
Questions worth asking
- Will you air seal the ceiling plane first, and what is that priced at separately?
- Does the old insulation need to come out, and if so, which of the three reasons applies?
- Is there vermiculite up there?
- Are you fitting baffles at every eave?
- Will a depth ruler be left stapled to a truss?
- What R-value am I getting, and what does the next one up cost?
- How are the recessed lights being handled — are they IC-rated, or do they need dams?
- Is the attic hatch being sealed and insulated?
- Are the bath fans ducted to outside, or into the attic?
- Which utility rebates apply, and do you file the paperwork?
Common questions
How much does attic insulation cost?
About $1,350 to top up a 1,000 square foot attic to R-49 with blown cellulose, which is $1.35 a square foot. Starting from bare joists is $1,875, and having old insulation removed first takes it to $3,000 — removal alone runs $1 to $2 a square foot, more than the installation that follows. Blown fiberglass is slightly cheaper than cellulose, batts are more expensive, and spray foam is two to three times the price at the depths it is normally applied — though it is priced by the board foot rather than to an R-value, so the comparison is looser than it looks.
Should I air seal before insulating the attic?
Yes, and it is the single most useful thing on this subject. Insulation slows heat through a surface and does nothing about air moving through holes — and the holes are in the ceiling plane underneath, around top plates, wiring, pipes, the chimney chase, bath fans and recessed lights. Sealing afterwards means raking 14 inches of loose fill aside to find them again. Air sealing runs $200 to $1,500, is usually quoted separately, and a contractor who does not offer it has told you something.
Does old attic insulation need to be removed?
Usually not. Dry, uncontaminated insulation stays and new loose fill goes straight over it, so you pay only for the balance of the depth — which is why topping up is the cheapest route to code. Three things genuinely require removal: rodents have nested in it, it is wet or has been, or it is vermiculite. If a quote includes removal and none of those applies, ask why, because removal is $1 to $2 a square foot.
What is the best insulation for an attic?
For an open attic floor, blown loose fill — cellulose or fiberglass. It covers an irregular surface better than anything cut to size, it is the cheapest per R-value, and it is quick. Cellulose packs denser and resists air movement through it better; fiberglass weighs less, which matters over a ceiling that was not built to carry much. Batts are for cavities or a floor somebody walks on, and spray foam belongs on a roof deck or in a crawl space rather than on an attic floor.
What R-value should attic insulation be?
R-49 across most of the US, which is the current code minimum, with R-38 enough in the warm South and R-60 worth having in the far North. The useful part is how little the choice costs: depth scales the material and barely touches the labor, so going from R-49 to R-60 adds about 10% to the job. If you are in a cold climate and the hose is already in the attic, it is the cheapest upgrade available.
What does vermiculite insulation look like and is it dangerous?
Small gray-brown or gold pebbles, or accordion-like flakes, poured rather than blown, and common in houses insulated between the 1920s and the 1990s. Most US vermiculite came from a mine at Libby, Montana that was contaminated with asbestos, and the EPA's advice is to assume it contains asbestos and leave it alone unless tested. Do not disturb it and do not let a crew blow insulation over it without a conversation — have it sampled by an accredited lab first, not by the insulation contractor.
Can insulation block attic ventilation?
Easily, and it is a real failure rather than a cosmetic one. Loose fill blown toward the eaves will bury the soffit vents, and a roof that cannot breathe gets condensation on the underside of the deck in winter — a common cause of ice dams in a house that has just been insulated. The fix is a baffle stapled between the rafters at every bay to hold the insulation back and keep the channel open. Ask whether they are being fitted, and check from the ground afterwards that the soffit vents are still vents.
How long does attic insulation take to pay for itself?
Ten to fifteen years in a mixed climate: heating and cooling is roughly half of a typical $1,400 to $1,800 energy bill, and taking a poor attic to R-49 saves perhaps 10 to 15% of that, or $85 to $130 a year against a $1,350 job. In a cold climate with an attic at R-11 and expensive fuel it can be four to six years. Over an attic that already has R-30 in a mild climate, the money is better spent elsewhere. What people actually notice is upstairs rooms matching downstairs ones.
Is there still a tax credit for attic insulation?
Not federally. Section 25C, which gave 30% of the cost of insulation and air sealing, was repealed for anything placed in service after 31 December 2025, and most pages on this subject have not caught up. What remains is utility rebates, which are often substantial and usually filed per project by the contractor, state and local programs, and income-qualified weatherization assistance that in some states covers the whole job. Ask your utility before booking the work rather than after.
How do I know how much attic insulation I need?
Measure the ceiling below rather than the roof: a 1,500 square foot single-story house has about a 1,500 square foot attic, and the same house over two floors has about 750. For depth, look at what is there now against the joists — standard joists are around 10 inches deep, so insulation level with the tops is roughly R-30 in loose fill and you need another four to six inches for R-49. Ask for a depth ruler to be stapled to a truss so you can check what you got.
Can I insulate my attic myself?
The blowing part, yes — the machines rent for about $100 a day, often free with enough bags, and the work is not skilled. Two things make it worth paying somebody: it is hot, itchy, awkward work in a confined space with a hose, and the parts that matter most are the parts that are easy to get wrong — air sealing the ceiling plane first, baffles at every eave, a dam around the hatch and around non-IC-rated cans, and even depth throughout. If you do it yourself, do those four things properly and the blowing will look after itself.
Should recessed lights be covered with insulation?
Only if they are IC-rated, which means rated for insulation contact and marked as such inside the housing. An older non-IC can buried in loose fill is a fire risk, so it needs a dam built around it or, better, replacing with a modern airtight IC-rated or canless LED unit. Old cans are also among the largest air leaks in a ceiling, so this is a job worth combining with the insulation rather than deferring — the attic is open and the crew is there.
Where these numbers come from
Nothing here is copied from a contractor directory. Labor is priced from what the trades are actually paid, materials from published producer prices, and both are adjusted to your area using federal cost-of-living data.
- Drywall and insulation contractors, United States: $39.00/hour, August 2026 (BLS CES CES2023831003)
- Blown cellulose to R-49: $0.60 per sq ft (price recorded October 2026, not index-adjusted)
- Baffles, dams, netting and masking: $0.15 per sq ft (price recorded October 2026, not index-adjusted)