Fast, Reliable Spray Foam Insulation Across Selma
Spray foam insulation in Selma, TX typically runs $1,800-$4,500 for most residential attic retrofits, with open-cell foam at $1.20-$1.80 per board foot and closed-cell at $2.50-$3.80 per board foot. Most Selma homes built during the 2005-2015 I-35 corridor boom were insulated to code-minimum R-30 with blown fiberglass that has since settled, and our crews can usually assess, price, and begin work within 48 hours. Call (830) 529-7780 - a live person answers, and we’ll dispatch from our San Antonio office to your Selma home with a written price before any work starts.
We’ve worked the same builder-grade floor plans across Selma’s subdivisions - Bridlewood, The Meadows, Woodbridge - and we know the truss geometry repeats street to street. That predictability means we can spot the problems faster and specify the fix without guesswork.
Why Topside Attic Insulation Boerne Is Selma’s Preferred Spray Foam Insulation Company
Our Spray Foam Insulation in Selma work is built on seeing the same house a hundred times. Not identical houses - the same house, built by the same national volume builders to the same plans, with the same low-heel open-web trusses and the same unsealed top plates. We’ve sealed and insulated over 9,000 homes since 2016, and enough of them have been in Selma’s I-35 corridor subdivisions that we don’t waste time figuring out what we’re walking into.
Response time to Selma is same-day or next-day for assessments. Our crews leave San Antonio with the materials and baffling stock needed for Selma’s specific truss geometry, so we’re not making supply runs while your attic sits open. Reviews from Selma customers consistently mention the blower-door numbers we leave behind - the pressurization reading that shows, in one figure, how much conditioned air the home was losing before and after our work.
Under Haven Standard Clause 1, every Selma job starts with a written price, flat scope, and written warranty before anyone lifts a tool. No exceptions. We also provide a Free Second Opinion on any written estimate from another contractor - bring us their scope and we’ll read it with you, line by line.
Our Spray Foam Insulation Services in Selma

Open-Cell Spray Foam
Open-cell spray foam is what we use most often in Selma’s vented attics - it’s vapor-permeable, expands to fill irregular cavities, and at roughly $1.20-$1.80 per board foot installed, it fits the retrofit budget for most 1,800-2,400 square foot tract homes. In Selma’s Climate Zone 2 conditions, open-cell on the roof deck or ceiling plane creates an air barrier that stops the 150°F attic heat from radiating into conditioned space. We source open-cell products from Icynene and Demilec - no proprietary lock-in, so we match the material to the assembly, not the other way around.

Closed-Cell Spray Foam
Closed-cell foam at $2.50-$3.80 per board foot is our choice for unvented crawl spaces, rim joists, and any application where vapor control matters. In Selma’s slab-on-grade construction, closed-cell at the rim joist blocks both air leakage and ground moisture wicking through block walls. The higher density also adds structural rigidity, which matters in garage ceiling applications where the builder’s drywall-only assembly needs real support.

Rim Joist Spray Foam
Selma’s post-2000 slab homes have rim joists that were rarely sealed by the builder - a gap at the perimeter where the sill plate meets the block wall, leaking conditioned air into the garage and exterior walls year-round. We spray closed-cell foam to seal this junction, typically 2-3 inches to achieve both air barrier and vapor retarder performance. It’s a small area but outsized impact; on blower-door tests, rim joist sealing alone often accounts for 300-600 CFM50 reduction.

Garage Ceiling Spray Foam
This is the Selma retrofit we wish more homeowners asked about. National builders in Selma’s 2005-2015 subdivisions finished garage ceilings with drywall directly against the truss bottom chord - no insulation, no air barrier, nothing between the 150°F attic and the bedrooms below. We remove or work around the drywall, spray open-cell foam to the full cavity depth, and restore the ceiling. The temperature drop in the rooms above is immediate and measurable. In Bridlewood off Old Austin Road, we measured a 12°F reduction in master bedroom surface temperature after garage ceiling foaming on a 2008 build.

Spray Foam Roof Deck
For Selma homeowners converting vented attics to conditioned storage or living space, we spray open-cell foam directly to the roof deck sheathing, creating an unvented assembly that brings the attic inside the thermal envelope. This requires careful moisture management - we specify vapor-permeable assemblies and, where code requires, supplemental dehumidification. Every unvented attic retrofit includes before-and-after blower-door numbers so you can verify the air-sealing result.

What happens when you call
- 1
A real person answersNo phone trees - you reach a local pro.
- 2
You get an upfront price rangeHonest numbers before anyone is dispatched.
- 3
A background-checked tech heads outLicensed & insured, dispatched right away.
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You approve before work beginsNothing starts until you say go.
Trusted Brands We Service in Selma
We install spray foam systems from Icynene, Demilec, and Owens Corning - brands we stock locally so Selma jobs aren’t waiting on freight from Houston or Dallas. No proprietary product lock-in means we specify based on your assembly’s needs: open-cell from Icynene for vented attic ceiling planes where vapor permeability matters; Demilec closed-cell for rim joists and garage ceilings where vapor control and compressive strength are priorities; Owens Corning systems where specific fire-rating or code compliance requirements apply. Our San Antonio warehouse keeps common densities and yields in stock for Selma’s typical 1,800-2,800 square foot retrofits, so crew downtime is minimal and your job moves on schedule.
Common Spray Foam Insulation Problems We See in Selma Homes

- Blocked soffit ventilation from unbaffled spray foam. Selma’s low-heel open-web trusses leave barely 4-6 inches at the eave. Installers who skip baffling spray foam right to the soffit, killing airflow and trapping moisture. We baffled every eave bay on a Bridlewood job last summer - the homeowner’s previous contractor had blocked 60% of soffit intake.
- Spray foam applied over unsealed top plates. The builder’s original crew blew fiberglass over top plates that were never caulked or foamed. Adding spray foam without sealing first just caps a leaking ceiling plane. Our protocol: air-seal top plates, can lights, and all penetrations before any insulation goes in.
- Garage ceilings radiating attic heat into bedrooms. Drywall-only garage ceilings in Selma’s tract homes let 150°F attic temperatures conduct straight through. Homeowners blame the AC; the real problem is the uninsulated thermal bridge one floor down.
- Settled blown fiberglass masquerading as adequate insulation. Original R-30 blown fiberglass in Selma’s 10-20 year old homes has settled to R-19 or worse. Spray foam retrofitted without assessing the existing condition wastes money - we remove or compress-settle the old material and start with a clean, sealed cavity.
Pricing for Spray Foam Insulation in Selma, TX
| Application | Price Range (Installed) | Typical Selma Home Size |
|---|---|---|
| Open-cell attic ceiling (vented) | $1,800 - $3,200 | 1,800-2,400 sq ft living |
| Open-cell roof deck (unvented) | $2,800 - $4,500 | 1,800-2,400 sq ft living |
| Closed-cell rim joist | $800 - $1,400 | Standard slab perimeter |
| Garage ceiling (open-cell) | $1,200 - $2,200 | 2-car, 400-500 sq ft ceiling |
| Closed-cell crawl space walls | $2,000 - $3,500 | 1,500-2,500 sq ft footprint |
These ranges reflect Selma’s typical tract-home geometry - low-heel trusses, standard room counts, straightforward access. What moves a job to the higher end: extensive existing insulation removal, multiple can-light air-sealing assemblies, or conditioned attic conversions requiring mechanical ventilation upgrades. Every Selma job gets a Written Price Before Any Work Starts - Haven Standard Clause 1 - with no change orders unless you add scope. We also provide a Free Second Opinion on any competing written estimate; bring it to us and we’ll review the material specs, coverage rates, and air-sealing protocol line by line.
We Also Serve Cities Near Selma

Our Spray Foam Insulation crews work across the northeastern San Antonio metro, including Boerne, Fair Oaks Ranch, Scenic Oaks, and Helotes. Each market has different housing stock and code eras - Boerne’s hill-country builds present different envelope challenges than Selma’s slab-on-grade tract homes - and we price and specify accordingly.
Serving Selma, TX - Our Local Coverage Area
We’re based in the Selma area and know this community well. Use the map below to see our service coverage - if you’re nearby, we can almost certainly help.
FAQs - Spray Foam Insulation in Selma

Yes, almost certainly. Selma’s 2005-2015 subdivisions used open-web roof trusses with pre-IRC-2012 low heel heights, leaving too little eave depth for full foam coverage without blocking soffit ventilation. We baffled every eave bay on a 2008 Bridlewood home last year - the previous installer hadn’t, and 60% of soffit intake was dead. Call (830) 529-7780 for an assessment; estimates are free and we’ll show you the truss geometry we’re working with.
Your builder’s R-30 blown fiberglass has settled to roughly R-19 after 10-20 years, and it was installed over unsealed top plates that leak conditioned air continuously. Spray foam air-seals and insulates in one application, stopping both conductive heat gain and convective air loss. In Selma’s 150°F+ attic conditions, that air-sealing matters as much as the R-value - our blower-door tests typically show 40-60% reduction in air leakage after proper foam and sealing.
Yes, and it’s one of the most impactful retrofits we do in Selma. National builders finished garage ceilings with drywall-only assemblies - no insulation, no air barrier - so attic heat radiates straight into bedrooms above. We spray open-cell foam to the cavity depth and restore the ceiling; surface temperatures in the rooms above typically drop 10-15°F immediately. Call (830) 529-7780 to schedule a garage ceiling assessment.
Spray foam alone won’t prevent freeze damage, but proper air-sealing combined with insulation dramatically reduces the risk. Winter Storm Uri exposed how poorly sealed Selma’s newer construction was - pipes burst in homes less than 15 years old because cold air infiltrated through rim joists, top plates, and can lights. We seal first, then insulate, which is the only protocol that addresses both the heat loss and the air leakage that carries it.
We install Icynene, Demilec, and Owens Corning spray foam systems - no exclusive arrangements, so we specify based on your assembly’s requirements. Icynene open-cell for vented attic ceilings where vapor permeability matters; Demilec closed-cell for rim joists and garage ceilings; Owens Corning where specific fire ratings or code compliance requirements apply. All materials are stocked locally for Selma jobs, not drop-shipped.
Written by Wes Okafor, Owner at Topside Attic Insulation Boerne, serving Selma since 2016 under The Haven Standard.