Washtenaw County specialists. U of M-area homes, Ypsilanti ranches, and newer Saline builds. Same-week estimates.
Quick answer: Spray foam insulation in Ann Arbor costs $1.00–$1.60 per board foot for open-cell and $1.60–$2.60 per board foot for closed-cell. Most homeowners pay $3,000–$6,500 for a combined attic and rim-joist treatment. Most jobs finish in one day. Final pricing depends on access, required thickness, and any removal of existing insulation.
University of Michigan expansion drove Ann Arbor's growth from the 1950s through the early 1980s. Ranch homes, cape cods, and split-levels went up fast to house faculty, staff, and growing families. The construction methods were standard for the era: 2x4 stud walls, 3.5 inches of fiberglass, no air barrier, and rim joists left open to the basement. That combination performs reasonably well in mild climates. It is not adequate for Zone 5A winters, where inside-outside temperature differentials exceed 70 degrees for weeks at a time.
The homes in Glacier Hills, Sycamore Hills, and along Huron Parkway are exactly this vintage. Their insulation was installed when energy was cheap and no one modeled air infiltration. Spray foam closes the gap between what was built and what a Michigan winter requires.
The two failure points we see most in Ann Arbor are the rim joist and the attic.
Rim joists in the 1960s and 1970s Ann Arbor builds are typically 9.25 inches deep and run the full perimeter of the house. Fiberglass batts stuffed into that cavity do not air-seal it. Cold air migrates freely around the batt edges. Closed-cell spray foam applied directly to the joist face and the foundation wall above the mudsill eliminates that path entirely. The improvement in first-floor temperature is usually immediate.
The attic problem is specific to cape cods and the cathedral-ceiling ranch homes that were popular in Ann Arbor in the 1970s. Those homes have complex roof geometry — dormers, knee walls, attic kneespace — that makes conventional insulation difficult to detail correctly. Open-cell spray foam applied to the underside of the roof deck converts the whole attic to conditioned space, eliminating the heat-loss paths that knee wall batts miss. Homes in Burns Park and the Old West Side, where the cape cod is the dominant building type, see the largest attic improvements.
DTE Energy's Home Performance with ENERGY STAR program covers air sealing work when paired with a certified energy audit. Ann Arbor DTE Energy and Consumers Energy offer rebates for qualifying insulation and air-sealing upgrades through their Home Energy Efficiency programs; amounts vary by measure and change annually, so confirm current amounts at dte.com or consumersenergy.com. A home energy audit may also qualify for utility incentives. Third-party energy raters active in Washtenaw County can walk you through the qualification steps before any work begins.
Ann Arbor's median home price has held above $450,000 since 2022. Real estate appraisers here now document air sealing and insulation upgrades as value-adds. The ROI calculation for spray foam in Ann Arbor includes both utility savings and a measurable effect on appraised value at sale.
Ranch homes and cape cods in Ann Arbor typically have full, deep basements — 8 to 9 feet in the mid-century builds. The rim joist runs 24 to 30 inches above grade on many of these homes, which means significant exposed surface area. Closed-cell spray foam at 2 inches creates an air seal and a Class II vapor retarder simultaneously. The basement holds heat in winter and stays dry in summer without additional vapor control.
Cape cods with attic kneespace and 1970s ranches with sloped ceilings are the most common applications we see here. Open-cell foam at the underside of the sheathing converts unconditioned attic space to conditioned. Heat pumps and mini-splits that are replacing gas furnaces in Ann Arbor need a tighter envelope to perform efficiently — spray foam makes the new HVAC math work.
The 1910s through 1940s craftsmans and colonials in the Old West Side and Kerrytown neighborhoods have different problems than the post-war stock: no house wrap, original plaster on wood lath, and basement walls that may never have seen any insulation treatment. These homes require closed-cell foam at the foundation wall in addition to the rim joist. The foundation wall treatment is what prevents the seasonal moisture cycling that degrades floor structure over time.
Spray foam jobs in Ann Arbor:
A rim joist job on a 1,400 sq ft ranch footprint runs $1,200 to $2,500 installed. A cape cod attic conversion — underside of roof deck plus knee wall sealing — runs $2,500 to $4,500 depending on access and dormers. DTE Energy and Consumers Energy offer rebates for qualifying insulation and air-sealing upgrades through their Home Energy Efficiency programs; amounts vary by measure and change annually, so confirm current amounts at dte.com or consumersenergy.com.
We serve Ann Arbor and Washtenaw County. Free estimates with next-business-day response.
If your January DTE gas bill runs over $220 and your home was built before 1990, air sealing is the highest-ROI improvement available. Fill out the form below for a same-week estimate appointment.
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Spray foam insulation in Ann Arbor typically costs $1.00–$1.60 per board foot for open-cell and $1.60–$2.60 per board foot for closed-cell. Most homeowners pay $3,000–$6,500 for a combined attic and rim-joist treatment. Final pricing depends on access, required thickness, and any removal of existing insulation. Michigan Spray Foam Insulation provides free, no-obligation estimates with a written price before any work begins.
Ann Arbor sits in IECC Climate Zone 5A. Most of Lower Michigan logs roughly 6,200 to 6,900 heating degree days per year. Code requires R-49 minimum attic insulation under Michigan's residential energy code (IECC Zone 5A).
Closed-cell spray foam is best for rim joists, basement walls, and below-grade applications in Ann Arbor because it insulates and blocks moisture vapor in the same pass. Closed-cell spray foam delivers approximately R-6 to R-7 per inch; open-cell approximately R-3.5 to R-4 per inch. Open-cell foam is cost-effective for attic floors where vapor management is less critical. We assess each application and recommend the right product.
Most residential spray foam jobs in the Ann Arbor area complete in one day. A rim joist and basement wall application typically runs four to six hours. Foam is fully cured within 24 hours; occupants and pets should stay out during installation and for 24 hours after.
DTE Energy and Consumers Energy offer rebates for qualifying insulation and air-sealing upgrades through their Home Energy Efficiency programs. Amounts vary by measure and change annually — confirm current amounts at dte.com or consumersenergy.com before your estimate. We can document the work in a format that supports your rebate application.
Tell us about your project and our crew will get back to you with a written quote within one business day.
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