R-13 insulation typically costs $1-$3 per square foot installed when using fiberglass batts in an accessible wall or floor cavity; material-only prices are usually $0.40-$1.20 per square foot. The final estimate depends on insulation type, project size, removal needs, access, and local labor rates.
| Item | Low | Average | High | Notes |
|---|---|---|---|---|
| Fiberglass batt installed | $1.00/sq ft | $1.80/sq ft | $3.00/sq ft | Open, accessible cavities |
| Fiberglass batt material | $0.40/sq ft | $0.75/sq ft | $1.20/sq ft | Before labor and waste |
| 500 sq ft installed | $500 | $900 | $1,500 | Standard batt installation |
| Removal and replacement | $1.50/sq ft | $3.00/sq ft | $5.50/sq ft | Includes old insulation removal |
What R-13 Fiberglass Insulation Costs Per Square Foot
For standard fiberglass batts in open wall cavities, homeowners commonly pay $1-$3 per square foot for materials and installation. A 500-square-foot project therefore runs about $500-$1,500, with a typical quote near $900. Small jobs may cost more per square foot because contractors often apply a minimum charge.
R-13 batts are commonly used in 2-by-4 exterior walls and other cavities where that insulation rating is appropriate. Estimates assume normal access, no major air sealing or framing repairs, and midrange materials. Assumptions: typical U.S. labor rates, open cavities, standard fiberglass batts, no hazardous-material abatement. For an uncomplicated batt job, around $1.80 per square foot is a practical planning figure.
How Batt Materials, Labor, and Removal Shape the Quote
Contractor estimates may separate insulation, installation, preparation, and disposal, or combine them into one installed rate. Ask whether the quoted area is the wall’s gross area or the net area after subtracting doors and windows, and whether materials include a cutting allowance.
| Quote item | Typical range | What it covers | Pricing basis |
|---|---|---|---|
| Fiberglass batts | $0.40-$1.20 | R-13 product and ordinary cutting waste | Per sq ft |
| Installation labor | $0.60-$1.80 | Fitting batts around framing and services | Per sq ft |
| Old insulation removal | $0.50-$2.50 | Bagging and removal of existing material | Per sq ft |
| Air sealing and prep | $0.25-$1.00 | Sealing accessible gaps before installation | Per sq ft |
| Disposal or trip charge | $75-$300 | Hauling, disposal, or small-job minimum | Per project |
Labor rates often fall around $50-$100 per worker-hour, but insulation crews usually quote by area rather than time. Removal, air sealing, and a minimum service charge can raise the bill beyond the batt price itself.
Which Wall Depth, Access, and Insulation Type Change the Price
R-13 fiberglass is generally sized for standard 2-by-4 framing, but cavity depth and framing irregularities affect fit and labor. Narrow bays, corners, wiring, plumbing, and obstructions require more cutting; densely packed cavities may not achieve the intended rating. Confirm that the product thickness and installation method suit the actual framing.
Material choice also changes the estimate. Mineral wool batts may cost roughly $1-$2.50 per square foot installed, while closed-cell spray foam that delivers approximately R-13 often costs about $3-$6 per square foot installed, depending on thickness and access. Spray foam is not a direct price-for-price substitute: air sealing, code requirements, and the specific assembly matter. Hard-to-reach cavities and foam applications can cost substantially more than open-wall fiberglass.
Job size has a measurable effect: a 100-square-foot repair may be billed at a $200-$500 minimum, while a 1,000-square-foot open-wall job can approach $1,000-$2,500 at common batt rates. Removing contaminated or pest-damaged insulation requires separate assessment and can increase disposal charges.
How R-13 Installation Prices Shift Across U.S. Regions
Labor and disposal rates make regional estimates differ even when batt prices are similar. As a broad comparison, installation may run 10%-20% below national-average pricing in lower-cost rural markets, while dense coastal cities can be 15%-35% higher. These are planning differences, not guaranteed regional tariffs; local contractor availability and job access can outweigh the regional average.
For example, a straightforward 500-square-foot batt installation priced at $900 in a mid-cost market might come in around $720-$810 in a lower-cost area or $1,035-$1,215 in a high-cost city. Travel, parking, building access, and local disposal rules can add charges. Compare quotes from contractors serving the same area and using the same scope before judging the price difference.
How Long a 500-Square-Foot Batt Job Takes
With open, unobstructed cavities, a two-person crew may complete 500 square feet in about 4-8 hours, including basic fitting and cleanup. Cutting around numerous pipes or electrical boxes, working overhead, or handling multiple small rooms can extend the job to a full day or longer. Occupied homes may also require extra protection and room-by-room scheduling.
Time estimates change sharply if old material must be removed. Removal, bagging, and disposal may add several hours, while air sealing and repairs add time according to the number of gaps and damaged areas. A quote that lists labor scope and expected crew time is easier to compare than a square-foot rate alone.
Three R-13 Quotes for Different Wall Projects
| Example | Scope | Estimated total | Rate |
|---|---|---|---|
| Small repair | 150 sq ft, open cavities, 4 labor hours | $300-$500 | $2.00-$3.33/sq ft |
| Typical room addition | 500 sq ft, standard batts, 6 labor hours | $700-$1,100 | $1.40-$2.20/sq ft |
| Replacement project | 800 sq ft, removal plus new batts, 12 labor hours | $1,600-$3,200 | $2.00-$4.00/sq ft |
These examples assume a crew rate near $50-$100 per worker-hour and ordinary access; the totals are illustrative, not fixed bids. The replacement example includes a wider range for old-material removal and disposal. Use the project’s net insulated area, not the home’s total floor area, when checking a per-square-foot quote.
When Removal, Air Sealing, or Difficult Access Adds Fees
Old insulation removal commonly adds $0.50-$2.50 per square foot, with higher charges possible for heavy contamination, tight crawlspaces, or difficult hauling. Ask whether the contractor includes bagging, disposal fees, and cleanup. If the insulation is wet or moldy, the source of moisture should be corrected before new material is installed.
Air sealing may add roughly $0.25-$1 per square foot when performed alongside insulation, although contractors may price it by the opening or hour. Moving stored items, protecting finished surfaces, or opening and closing walls can also add labor. Have the estimate identify each extra task so removal or repair fees do not appear unexpectedly on the final invoice.
Ways to Lower an R-13 Insulation Estimate
Get at least three written quotes with matching assumptions for square footage, insulation type, removal, air sealing, cleanup, and warranty. Ask contractors to show the material and labor charges separately, and check whether the stated price includes taxes or a trip minimum. Bundling adjacent rooms or exterior walls may reduce mobilization charges.
Where walls are already open, installing batts before drywall is generally less expensive than accessing finished walls. Handle simple room clearing and movable-item preparation in advance, but leave wiring, moisture issues, and code-related work to qualified trades. Avoid paying for a higher-cost insulation system unless its performance or air-sealing benefit is needed for the specific assembly. Controlling access and scope usually saves more than choosing the cheapest batt without comparing installation details.