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

Fast, Reliable Spray Foam Insulation Across Kirby

Spray foam insulation in Kirby, TX typically runs $1,800-$4,500 for attic and rim-joist work on a mid-century ranch, with most jobs completed in one day. We’re Envelope Insulation Co., and our Spray Foam Insulation crews serve Kirby from our San Antonio dispatch office - usually on-site within 45 minutes of a scheduled arrival. Call (830) 243-6352 for a written price before any work starts.

Call (830) 243-6352

Kirby’s a unique job site. This fully built-out enclave city, completely surrounded by San Antonio, is packed with 1950s-1970s slab ranch homes that were thrown up during Bexar County’s mid-century boom with little or no attic insulation and zero wall cavity fill. Those original fiberglass batts - if they’re still there - have been cooking at 150°F for sixty-plus summers. We see it on Seguin Road, on Gibbs Sprawl, in the neighborhoods around Kirby Middle School: compressed, dirty, sometimes moldy insulation doing almost nothing while attic ducts bleed conditioned air into a 145°F void. That’s the reality we’re fixing.

Why Topside Attic Insulation New Braunfels Is Kirby’s Preferred Spray Foam Insulation Company

We’ve sealed and insulated over 9,000 homes since 2016, and Kirby’s mid-century stock is some of the most straightforward upgrade value we find in Bexar County. The homes are simple ranch boxes on slabs - no complex rooflines, no cathedral ceilings - which means we can move fast and document real results. On every applicable job we run a blower-door test, a pressurization reading that shows, in one number, how much air your building envelope is losing. We publish the before-and-after figures so you can verify the performance change you paid for.

Our Kirby customers find us because they’ve already talked to San Antonio crews who didn’t know Kirby runs its own permitting. That’s a dead giveaway. We’ve pulled dozens of city of Kirby permits specifically - not Bexar County, not San Antonio - and we know the inspectors by name. Our 365-Day Done Right Promise applies to every job: if it’s not done right, we make it right, backed by a written scope and written warranty delivered before anyone lifts a tool. Haven Standard Clause 1: flat price, written scope, written warranty. Always.

Calls are answered by a live person, 24/7. No voicemail loops. You’ll get a named technician and a text when they’re on the way. Background-checked, uniformed crews. And a Documented Photo Record on every visit - included, not available on request.

Our Spray Foam Insulation Services in Kirby

Closed-Cell Spray Foam

Closed-cell spray foam is our go-to for Kirby’s rim joists and roof decks. At roughly R-6.5 per inch, it packs the highest thermal resistance into the shallow cavities these ranch homes offer. We use it on slab foundations where the rim joist sits directly on concrete - a detail that pulls outdoor air and humidity into the wall cavity year-round. In Kirby’s climate, where cooling loads dominate and summer attic temperatures crack 140°F for weeks, closed-cell on the roof deck creates a conditioned attic that stops your ductwork from sitting in a convection oven. We source materials from Demilec and Johns Manville, among others - no proprietary lock-in, so we match the product to the cavity, not the other way around.

Open-Cell Spray Foam

Open-cell runs lighter and less dense, about R-3.6 per inch, and we use it in Kirby where cavity depth isn’t the constraint and budget is. It works for attic floors and some wall applications in homes where we’ve already air-sealed the top plates and can light penetrations. The tradeoff: open-cell is vapor-permeable, so we don’t spec it for rim joists or anywhere groundwater wicking is a concern. In Kirby’s older homes with original slab construction and no vapor barrier under the concrete, that’s a critical distinction we make on-site.

Rim Joist Spray Foam

The rim joist is the single most neglected leak in Kirby’s slab ranches. That band of wood where the floor trusses meet the exterior wall sits exposed to outdoor air, humidity, and - during events like the February 2021 freeze - brutal cold transfer. We see rim joists in Kirby homes with nothing but a strip of fiberglass batt stuffed in loosely, if that. Our crew removes the old material, cleans the cavity, and applies closed-cell spray foam to seal and insulate in one pass. On a typical 1,200-square-foot Kirby ranch, this is a same-day job with immediate blower-door improvement.

Garage Ceiling Spray Foam

Garage ceiling spray foam in Kirby matters because so many of these ranches have attached garages with bedrooms directly above. The garage ceiling is often uninsulated drywall or - worse - open joists with the subfloor exposed. In summer, that garage hits 110°F and radiates straight into the bedroom above. We spray the garage ceiling to create a thermal break, typically with open-cell for cost efficiency or closed-cell where fire separation is the priority. Alley-loaded lots on streets near Kirby City Park make rig access tricky, so we plan hose runs and parking before we arrive. Crews who don’t plan end up with incomplete coverage at the far end of the attic. We don’t let that happen.

Spray Foam Roof Deck

Spray foam on the roof deck is the upgrade that transforms a Kirby attic from a liability into a conditioned space. Instead of insulating the attic floor and leaving your ducts to roast, we foam the underside of the roof deck and bring the attic inside the thermal envelope. This is where Kirby’s shallow attic decks and old wiring create real challenges: knob-and-tube remnants and old BX cable are common in pre-1970 homes, and spray foam applied over live wiring without proper standoff creates code violations and heat-trapping hazards. We identify and address electrical clearances before we foam. The result: your HVAC equipment and ductwork operate in 80°F air instead of 145°F, and your cooling load drops measurably.

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Trusted Brands We Service in Kirby

We install spray foam systems from Owens Corning, Johns Manville, and Demilec - brands we stock for fast turnaround on Kirby jobs. No proprietary product lock-in means we select based on your cavity conditions, not our supplier contract. Every batch is documented with manufacturer data sheets, and we keep Kirby-specific stock on hand for common closed-cell rim-joist and roof-deck applications so we’re not waiting on freight while your attic sits open.

Common Spray Foam Insulation Problems We See in Kirby Homes

• Permits filed through San Antonio or Bexar County instead of Kirby’s own building department. Out-of-area crews assume the enclave falls under larger jurisdiction, then the job gets red-tagged mid-application. We pull city of Kirby permits from the start - it’s a separate process, and we know it.
• Original fiberglass batts compressed to R-5 or less after decades of 150°F heat cycling. In Kirby attics, we regularly pull out batts that are half their original thickness, black with dust, and holding moisture against the drywall ceiling. Spray foam replacement typically doubles the effective R-value in the same cavity depth.
• Live electrical buried under new spray foam. Kirby’s 1950s-70s wiring wasn’t designed for modern insulation contact. We inspect for knob-and-tube and ungrounded BX, coordinate electrician clearance when needed, and maintain code-required standoffs before foam touches anything.
• Incomplete coverage on alley-loaded lots with poor rig positioning. Kirby’s dense mid-century blocks have narrow side yards and street-parking constraints. Crews who don’t plan hose length and staging end up with cold spots at the attic’s far reaches. We measure and stage before we start.

Pricing for Spray Foam Insulation in Kirby, TX

We Also Serve Cities Near Kirby

Our crews work throughout the corridor: Kirby, New Braunfels, Cibolo, Seguin, and Schertz. Same written-price standard, same blower-door documentation, same live-answer dispatch. Wherever you’re located, the process doesn’t change.

FAQs - Spray Foam Insulation in Kirby