When choosing between spray foam insulation and fiberglass, buyers commonly ask about cost, price per square foot, and overall value. This comparison covers typical installed costs, per-square-foot pricing, and major drivers that shift a bid in either direction.
| Item | Low | Average | High | Notes |
|---|---|---|---|---|
| Total Installed Cost | $1.50 per sq ft | $2.50 per sq ft | $4.50 per sq ft | Attic or wall applications; see system type |
| Per Sq Ft Heat-Transfer Value | R-13 for walls | R-20 to R-38 for attics | R-40+ for premium builds | Rank depends on region and framing |
| Labor per Hour | $40 | $65 | $100 | Installer skill and regional rates |
| Materials | $0.50 | $1.10 | $2.00 | Foam type and delivery method |
| Delivery/Disposal | $0.10 per sq ft | $0.25 per sq ft | $0.50 per sq ft | Packaging and waste handling |
Spray Foam Insulation Total Price Range for Attic and Walls
Typical installed costs for spray foam vary by application type, open-cell versus closed-cell formulations, and whether the project covers attic knee walls, rim joists, or full-wall cavities. In common U.S. homes, expect $2.00 to $4.00 per sq ft for full coverage, with closed-cell options trending higher. Regions with strict energy codes or larger open areas can push price toward the upper end. A standard 1,000 sq ft attic with a mid-range closed-cell profile might land around $2,400-$3,800, while open-cell configurations in the same space could run $1,800-$2,900. Assumptions: Midwest labor rates, standard 2×4 wall framing, normal access.
Fiberglass Insulation Price Range by R-Value and Area
Fiberglass insulation costs are generally lower upfront, with typical installed ranges of $0.60 to $1.30 per sq ft for batts or loose-fill in standard homes. For an attic or wall retrofit aiming for R-13 to R-23 in walls and R-38 in attics, total installed pricing commonly sits between $1.50 and $2.50 per sq ft, depending on thickness, vapor barrier needs, and whether a professional blower or dense-pack method is used. A 1,000 sq ft attic example might be $1,000-$2,500, when labor and materials are included. Assumptions: Suburban crew, standard joist spacing, existing reach.
Major Cost Components in a Spray Foam Quote
| Component | Low | Average | High | Notes |
|---|---|---|---|---|
| Materials | $0.60 | $1.20 | $2.00 | Open-cell vs closed-cell, yield per canister |
| Labor | $1.50 per sq ft | $2.40 per sq ft | $3.80 per sq ft | Application time, crew size |
| Equipment | $0.10 | $0.25 | $0.60 | Spray rig, hoses, safety gear |
| Permits | $0 | $0.10 | $0.50 | Local building permits if required |
| Delivery/Disposal | $0.05 | $0.20 | $0.40 | Material handling |
| Warranty/Contingency | $0.10 | $0.20 | $0.40 | Labor guarantees, material claims |
Fiberglass Cost Elements and Labor Allocation
| Element | Low | Average | High | Notes |
|---|---|---|---|---|
| Batts/Blankets | $0.40 | $0.75 | $1.25 | R-value dependent |
| Labor | $0.50 per sq ft | $0.90 per sq ft | $1.50 per sq ft | Cutting, fitting, stapling |
| Vapor Barrier/Facings | $0.05 | $0.15 | $0.30 | Plastic sheeting, kraft paper |
| Waste Handling | $0.02 | $0.08 | $0.15 | Waste and disposal |
| Tools/Equipment Use | $0.03 | $0.08 | $0.20 | Sealants, staples |
Key Variables Driving Final Quotes for Spray Foam and Fiberglass
Size and access are major price levers; larger homes or cramped crawlspaces drive higher labor hours. A third-party blower or specialty spray foam equipment can push costs up if access is limited. For fiberglass, projecting attic height and the number of bays or angles often moves price more than raw material costs. If an attic has limited entry, or ducts must be removed, expect a 10–25% revenue shift on spray foam bids. Assumptions: Single-story home with standard attic access and common wall framing.
Ways to Cut Costs on Insulation Projects
Cost-reduction strategies include dialing back on higher-density spray foam in favor of open-cell where appropriate, bundling insulation with air sealing, planning work in mild seasons to reduce labor disruption, and comparing quotes with consistent scope. If a project allows, replacing only severely drafty areas or prioritizing performance-critical zones can lower the overall price. Assumptions: Standard scope with optional upgrades considered separately.
Regional Price Differences Across the United States
Prices vary by region due to labor markets, material sourcing, and permit rules. Coastal states may see higher installed costs for spray foam, while rural areas often have lower labor rates but longer travel times. Expect regional deltas of roughly ±20% between Midwest and West Coast for similar homes, and up to ±30% in high-cost metro areas. Assumptions: Typical single-family homes, standard ceiling height.
Labor Time and Unit Rates by Project Scope
Labor time estimates depend on whether the project is attic-only, walls-only, or a full retrofit. Attic-only spray foam may take 6–12 hours for a mid-sized home, while full-wall or full-house coverage can exceed 20 hours on a busy job. In fiberglass, labor usually runs lower per sq ft, with batts installed in bulk faster but may require more preparatory work. Assumptions: Two-person crew, typical weather window.
Per-Unit vs Per-Square-Foot Pricing Comparisons
Per-square-foot pricing is standard for both options, but occasional per-bay or per-room quotes help with budgeting. For spray foam, per-square-foot pricing often includes installation of air sealing and minor surface prep, whereas fiberglass may itemize per batt, per linear foot of wall, or per attic hatch. Example: attic patchwork at $1.50–$3.50 per sq ft for spray foam, $0.80–$1.60 per sq ft for fiberglass, depending on layout. Assumptions: Typical attic and wall coverage with standard finishes.