Two thirds of a professional insulation bill is labour, which is why the same material can cost twice as much in one assembly as another. An open attic floor is cheap because the work is quick; a finished wall costs more because somebody has to drill, fill and patch every stud bay.
Installed cost per square foot
At R-30. Bars show the typical range, so overlap is visible.
- $0.90–$2.10
- $1.05–$2.05
- $1.05–$2.10
- $1.35–$2.25
- $1.80–$3.20
- $3.00–$4.50
Insulation cost per square foot
$0.90–$3.20What every material costs installed, what a quote should include, and where the money goes furthest.
Read moreAttic insulation cost
Best returnThe cheapest R-value in the house. What a typical attic costs by size, DIY against installed.
Read moreBlown-in insulation cost
By the bagCellulose against blown fiberglass by the bag, including machine hire and what it saves.
Read moreSpray foam insulation cost
Board feetPriced in board feet, the unit foam is actually quoted in. Open cell against closed cell.
Read moreWall insulation cost
Access decidesOpen framing against drill-and-fill. The premium on a finished wall is access, not material.
Read moreGarage insulation cost
2 of 5 surfacesWhich of the five surfaces actually affect your bill, and the fire-rated drywall most quotes omit.
Read moreCrawl space insulation cost
Two routesFloor insulation against full encapsulation — different projects, roughly five times apart in price.
Read moreBasement insulation cost
Below gradeRigid foam against closed-cell on below-grade walls, and the assembly that reliably grows mould.
Read moreCellulose insulation cost
By the bagPer square foot and per bag, what the blower hire adds, and why small jobs cost more per foot.
Read moreFiberglass insulation cost
Batts & blownBatts and blown priced separately, what a pack actually covers, and why a sloppy fit costs the saving.
Read moreMineral wool insulation cost
The premiumRoughly double fiberglass. What the premium buys in fire and sound, and where it is worth paying.
Read more
Where our figures come from
Every range on this site is built from published material properties and national average labour rates, and the arithmetic is shown on each calculator's result. They are planning figures, not quotes — local labour rates move them more than anything else.Our methodology sets out every assumption.
What a quote tends to leave out
- A minimum job charge. Around $400–$700 for general work and $800–$1,500 for drill-and-fill. Staging and patching do not scale down, so one cold wall can cost nearly what a whole elevation would. Price the rest at the same time.
- Removing what failed. Crawl space batts sag out of contact and soak up damp; attic insulation gets nested in. Removal runs its own rate before anything new goes in.
- Drywall that has to go back. IRC Table R302.6 requires gypsum on the garage side, ⅝ inch Type X under habitable rooms. Opening a common wall means paying to close it.
- Air sealing. Cheap, done before the insulation, and unreachable afterwards. Insulation laid over an unsealed ceiling underperforms its rating.