Fiberglass cost per square foot depends on whether the purchase is insulation, roofing, or a molded panel; insulation is the most common home-project estimate. Fiberglass insulation typically costs $0.80-$2.50 per sq ft installed, with higher totals for difficult access, removal, or high-R-value upgrades. The figures below separate insulation pricing from other fiberglass products so estimates can be compared on the same basis.
| Item | Low | Average | High | Notes |
|---|---|---|---|---|
| Fiberglass batt insulation, installed | $0.80/sq ft | $1.50/sq ft | $2.50/sq ft | Open, accessible walls or ceilings |
| Blown-in fiberglass, installed | $1.00/sq ft | $1.75/sq ft | $3.00/sq ft | Attic or enclosed cavity; depth affects price |
| Fiberglass insulation materials only | $0.30/sq ft | $0.80/sq ft | $1.50/sq ft | Product and R-value vary |
| Fiberglass roofing panels | $2/sq ft | $4/sq ft | $8/sq ft | Panels only; framing and installation extra |
Assumptions: U.S. pricing for standard products and ordinary access; regional labor, project size, and removal can change totals.
What fiberglass insulation costs for a typical home project
Most homeowners pay about $1.50 per sq ft for installed fiberglass insulation. A 500-sq-ft attic or wall area therefore runs roughly $400-$1,250, before unusual repairs or disposal. Batt insulation is commonly used in open stud bays; blown-in fiberglass suits many attics and closed cavities. Material-only prices are lower, but DIY work must account for protective gear, cutting waste, equipment rental, and fitting around wiring and framing.
R-value, or thermal resistance, influences the quantity and product cost. Standard wall batts often cost less per square foot than thicker attic insulation. The estimate should identify the product type, R-value, coverage area, and whether labor, air sealing, or old-insulation removal is included.
How batt materials and installation shape the quote
Labor and access can cost as much as, or more than, the fiberglass itself. Typical component ranges for a straightforward installation are:
| Quote component | Low | Average | High | Pricing basis |
|---|---|---|---|---|
| Fiberglass batts or rolls | $0.30/sq ft | $0.80/sq ft | $1.50/sq ft | R-value and facing |
| Installation labor | $0.50/sq ft | $1.00/sq ft | $2.00/sq ft | Access and detail work |
| Blower or equipment | $50/job | $150/job | $350/job | Often included in blown-in bids |
| Removal and disposal | $1/sq ft | $2/sq ft | $4/sq ft | Existing material and contamination |
| Air sealing supplies and work | $0.20/sq ft | $0.60/sq ft | $1.50/sq ft | Depends on gaps and penetrations |
Labor can also be quoted by time, commonly around $40-$85 per worker-hour, with crew size and minimum charges affecting smaller jobs. Confirm whether the quote includes cleanup, disposal fees, and protection of nearby fixtures.
R-value, thickness, and cavity size change the price
Higher R-values and tight or irregular cavities raise material and labor costs. Moving from R-13 to R-21 wall batts may add roughly $0.20-$0.70 per sq ft, depending on product and local availability. Attics needing R-38 to R-60 require more depth and material than a basic top-up; blown-in fiberglass is often priced by installed area and target depth.
Open, empty stud bays are faster to fill than finished walls that require drilling and patching. A 2-by-4 cavity generally accepts thinner batts than a 2-by-6 cavity. Water damage, wiring congestion, narrow access, or a roof pitch above about 8:12 can also add labor or prep charges.
How regional labor rates affect insulation prices
Local labor markets can shift an otherwise similar bid by about 10%-30%. High-cost metropolitan areas and regions with strong seasonal demand may price above national midrange, while some rural markets charge less but add travel or minimum-job fees. Climate affects the recommended insulation level rather than setting one nationwide price: colder regions commonly need more attic depth than mild-climate locations.
Ask contractors to quote the same square footage and target R-value. Compare labor, equipment, and disposal separately, because a low per-square-foot figure may exclude air sealing or existing material removal. For a small attic, a fixed minimum charge can make the effective rate higher than the advertised unit price.
What removal and attic preparation add to the bill
Old insulation, pest contamination, and repairs can add several dollars per square foot. Basic removal and disposal often runs $1-$4 per sq ft; wet, compacted, or contaminated insulation may require more careful handling and a separate remediation estimate. Ask whether the price includes bagging, haul-away, and cleaning rather than assuming removal is part of installation.
Air sealing around top plates, ducts, and openings may add about $0.20-$1.50 per sq ft, depending on how extensive the work is. Attic decking, recessed-light protection, ventilation corrections, and access-hatch insulation may appear as separate line items. These improvements should be priced individually so necessary building work is not confused with the fiberglass rate.
Three fiberglass insulation quotes at different project sizes
Project size and access explain why per-square-foot totals vary. These examples use typical U.S. pricing, not fixed national bids:
- Open garage ceiling: 400 sq ft of R-19 batts at $0.80 per sq ft for materials, plus 8 labor hours at $55 per hour, totals about $760, or $1.90 per sq ft.
- Accessible attic top-up: 1,000 sq ft of blown-in fiberglass at $1.40-$2.10 per sq ft installed totals $1,400-$2,100, assuming no removal or major air sealing.
- Finished-wall retrofit: 600 sq ft of cavity fill at $2.50-$5 per sq ft totals $1,500-$3,000, including access work and patching allowances; finish repairs may be separate.
How to lower the fiberglass price without cutting performance
Control the scope and compare equivalent R-values before choosing the lowest bid. Measure the area accurately, clear attic access beforehand, and request separate pricing for insulation, air sealing, removal, and repairs. Bundling multiple rooms can reduce mobilization costs, while scheduling outside peak weather emergencies may improve contractor availability.
Choose batts when framing is open and dimensions are regular; blown-in material may be more practical for large attic areas or hard-to-reach spaces. Avoid paying for unnecessary removal if existing insulation is dry, clean, and suitable to remain. For roofing panels or molded fiberglass, compare product thickness, coating, and structural support separately because insulation installation rates do not apply to those products.