Spray Foam Insulation in Boerne - Same-Day Service, Done Right the First Time

Fast, Reliable Spray Foam Insulation Across Boerne

Spray foam insulation in Boerne costs between $1.80 and $4.50 per board foot installed, depending on whether you choose open-cell or closed-cell foam. A typical rim joist job in Boerne runs $900 to $2,400, while a full attic spray foam project usually lands between $4,500 and $12,000. We serve Boerne homes with crews who know the difference between a limestone house off Main Street and a 2005 hardiplank build near Champion High School. Call us at (903) 437-9164 for a written price before any work starts.

Call (903) 437-9164

Boerne sits on the Balcones Fault Zone, and the expansive clay soil here moves more than most homeowners realize. That movement matters for spray foam work in ways it doesn’t in San Antonio. When a slab settles even half an inch, gaps open at the rim joist line and crawl space seams. Fiberglass batts can’t seal those gaps. Spray foam can, and it flexes with the house as the soil shifts through wet springs and dry summers.

Why Thistledown Insulation San Antonio Is Boerne’s Preferred Spray Foam Insulation Company

Thistledown Insulation San Antonio is a Cedarwell-family company founded in 2003. Neil Barron leads our crew, and every technician who walks into a Boerne home is background-checked, uniformed, and trained to the Cedarwell Care Promise. That means shoe covers from the front door to the attic hatch, drop cloths across your hallway, and a photo of the clean-up before we leave. We name the promise after how careful the job is: Thistledown is the soft fluff of the thistle, one of nature’s lightest insulators. The name is a promise about how carefully we work.

Boerne homeowners tell us two things consistently. They want to know exactly what product goes near the baby’s room, and they want the number in writing before anyone picks up a tool. We do both. Every quote is a written, line-item price. The 365-Day Done Right Promise backs every job: if it’s not done right, we make it right, no debate, no fine print. A live person answers our phone 24 hours a day, seven days a week. When you call at 9 p.m. on a Tuesday, you get a person, not a voicemail tree.

We work regularly in Boerne neighborhoods like Champion Heights, and our crews know the housing stock here. The older homes near Main Street may have little or no wall insulation. The 1980s and 1990s tract builds usually have fiberglass batts but poor attic sealing. The custom Hill Country estates have their own quirks. This fragmented landscape is exactly why one-size-fits-all insulation advice fails in Boerne, and why our Spray Foam Insulation team matches the foam type and application method to each house, not to a sales script.

Rim Joist Spray Foam in Boerne

Rim joist spray foam in Boerne is the single most cost-effective upgrade we perform for homes on expansive clay soil, because it seals the gap where the foundation meets the framed floor above. The rim joist is the band of wood that sits on top of your foundation wall. In Boerne, when clay soil expands after a wet spring and shrinks in a dry summer, the slab or pier-and-beam foundation moves. That movement opens tiny gaps along the rim joist line. Humid outdoor air seeps in, condenses on the underside of the subfloor, and creates the musty smell so many Boerne homeowners notice in closets and along baseboards.

We use closed-cell foam for rim joists in Boerne almost exclusively. Closed-cell foam has a higher R-value per inch and acts as its own vapor barrier. It air-seals the rim joist bay and holds tight even as the soil shifts. Open-cell foam does not offer the same moisture resistance for this application. A typical rim joist spray foam job in Boerne runs $900 to $2,400 for an average home, and most jobs take less than a day. Because we carry Demilec closed-cell foam on our trucks serving Boerne, we can often schedule the work within the same week.

Air Sealing Against Hill Country Humidity

During a Boerne summer, dew points often sit above 70°F while highs reach the 90s. That combination pushes humid air into any unsealed rim joist gap. Closed-cell spray foam stops that air movement. The result is a drier crawl space or basement, fewer musty odors, and less work for your air conditioner.

Pest Intrusion Prevention at the Foundation Line

Gaps along the rim joist are also an open door for rodents, roaches, and other pests common to the Hill Country. Closed-cell foam expands to fill the entire bay and cures hard, which makes it far less inviting to pests than fiberglass batts. A Boerne homeowner who sees a roach trail near the baseboards in July often has a rim joist problem, not a housekeeping problem.

Crawl Space Spray Foam Insulation in Boerne

Crawl space spray foam insulation in Boerne matters most for the pier-and-beam homes you’ll find in older neighborhoods and acreage properties, where the floor sits above a vented space open to outside air. In these homes, winter cold snaps that dip into the 20s can freeze plumbing in exterior walls and make floors brutally cold. A vented crawl space also lets humid Hill Country air circulate under the house all summer, which condenses on cool ductwork and framing. Spray foam on the crawl space walls and rim joists turns that space into a conditioned, sealed envelope.

For crawl spaces in Boerne, the sequence matters. The rim joist and band board must be addressed first, not as an afterthought. We spray closed-cell foam on the rim joist bays and band board, then insulate the crawl space walls. This closes the air gaps that let winter cold reach plumbing in exterior walls. A crawl space encapsulation with spray foam in Boerne typically costs $3,500 to $9,000 depending on square footage and access. Homes off River Road with tight crawl spaces or low clearance take longer, and we factor that into the written quote.

Freeze Protection for Pier-and-Beam Homes

Boerne pier-and-beam homes sit above ground with air moving beneath the floor. When the temperature drops into the 20s, that moving air freezes exposed pipes fast. Spray foam on the crawl space walls and rim joists keeps that air out and holds heat in. It is the difference between a cold snap and a plumbing repair.

Moisture Control Without a Full Encapsulation

Some Boerne homeowners assume they need a full plastic vapor barrier liner to fix a damp crawl space. Spray foam on the walls and rim joists often solves the humidity problem on its own by stopping outside air from entering. We will tell you honestly whether a liner adds value for your specific house, and the written price covers exactly what we recommend.

Trusted Brands We Service in Boerne

We install two spray foam product lines from Demilec: open-cell and closed-cell. Demilec closed-cell foam is our go-to for rim joists and crawl spaces in Boerne because of its moisture resistance and air-sealing strength. For homes where the family wants a plant-based, lower-VOC option, we also offer Demilec’s open-cell line and can discuss pet-safe choices where a choice exists. We also install attic insulation systems from Owens Corning and Johns Manville when a Boerne home needs a hybrid approach, such as spray foam on the roofline plus blown-in fiberglass on the attic floor. Having multiple brands on the truck means we match the product to the house, not the other way around.

Common Spray Foam Insulation Problems We See in Boerne Homes

• Soil movement opening rim joist gaps: Boerne’s expansive clay expands and contracts with every wet-dry cycle. That movement cracks open air gaps at the rim joist line where conditioned air leaks out and humid Hill Country air seeps in. Fiberglass batts can’t seal these gaps because they don’t flex with the foundation.
• Humidity-driven condensation in vented attics: In Boerne’s 1980s to 2000s tract homes, open-cell foam installed without a proper vapor barrier in a vented attic can absorb summer humidity. That leads to damp ceiling drywall, sagging paint, or mold. The foam type and ventilation strategy have to be matched to the specific attic.
• Frozen pipes in pier-and-beam crawl spaces: Winter nights in Boerne can drop into the 20s, and a pier-and-beam home with an unsealed crawl space exposes plumbing to that cold. Spray foaming crawl space walls but skipping the rim joist and band board still leaves pipes vulnerable.
• Historic limestone homes with no wall insulation: The limestone and wood-frame houses near Main Street often have no wall cavities to fill. The only practical way to add insulation is through the attic and roof deck, and spray foam is often the best tool. But before anyone sprays, our crew checks for limestone dust and bat guano in the attic, because both affect adhesion and safety.

Pricing for Spray Foam Insulation in Boerne, TX

We Also Serve Cities Near Boerne

Our crews serve homes throughout Boerne and the surrounding Hill Country, including San Antonio, Cibolo, New Braunfels, and Floresville. If you live just outside Boerne city limits, call us and we’ll confirm coverage for your address. Scheduling and dispatch are coordinated from our San Antonio office, with crews working locally in Boerne throughout the week.

FAQs About Spray Foam Insulation in Boerne