Insulation in San Antonio, TX
Crawl space encapsulation and vapor barrier installation in San Antonio runs $2,800-$6,500 for most homes, with jobs in the military-corridor tract housing of Converse and Universal City typically landing in the middle of that range. We’re Envelope Insulation Co., and we dispatch crews from our San Antonio office to handle the full building envelope: attic work, spray foam, blown-in, wall insulation, radiant barriers, crawl spaces, air sealing, removal and replacement, cleaning and rodent proofing, and home energy audits. Every job starts with a written price and ends with a documented photo record. Call (830) 420-0953 for a free estimate.
Why San Antonio Homes Are Different
San Antonio’s identity as Military City USA created rings of 1950s-70s federal-spec tract housing in communities like Converse, Universal City, and Leon Valley, nearly all built with R-11 or less in the attic. These homes now face attic temperatures regularly topping 140-160°F in summer, and Winter Storm Uri in February 2021 exposed how dangerously under-insulated they remain for cold. The retrofit demand concentrates in a specific housing era and geography with no equivalent in Austin or Houston.
The housing stock splits sharply. Central neighborhoods like King William, Monte Vista, and Dignowity Hill use pre-1940s limestone block or hollow clay tile with little to no cavity wall insulation, requiring interior rigid-foam retrofits. The post-WWII slab-on-grade wood-frame belt in military-adjacent corridors dominates the retrofit market. Newer north-side expansion in Stone Oak, Helotes, and Cibolo increasingly expects spray foam and radiant barriers as code baseline. San Antonio sits at the edge of the semi-arid Edwards Plateau, which means lower humidity than Houston but no relief from heat, making attic air sealing and radiant barrier installation the highest-ROI upgrades available.
Our Main San Antonio Services
San Antonio homeowners call us most often for attic work and spray foam. Here is what those jobs involve locally.
Attic Insulation in San Antonio
Attic insulation in San Antonio means dealing with 150°F+ cavity temperatures in July and August on low-pitched roofs common to mid-century military housing. We start with a blower-door test to measure air leakage, seal all top plates and penetrations, then install to current IECC code levels using Owens Corning, Johns Manville, or Knauf materials. Before-and-after blower-door numbers go to the homeowner in writing. Attic Insulation in San Antonio covers full pricing and scope details.
Spray Foam Insulation in San Antonio
Spray foam insulation in San Antonio addresses the eight-month cooling season directly by creating an air-impermeable thermal boundary at the roof deck or walls. We use open-cell and closed-cell products from Icynene and Demilec, selected by application, never pushed as a proprietary solution. Every spray foam job gets a written scope, documented photos, and the 365-Day Done Right Promise. Spray Foam Insulation in San Antonio has full technical specifications.
Blown-In Insulation in San Antonio
Blown-in insulation in San Antonio remains the most common retrofit for the military-corridor housing stock with undersized original batts. We blow fiberglass or cellulose from GreenFiber and CertainTeed only after air sealing is complete, never over unsealed attic floors. The blower-door test proves the result. Blown-In Insulation in San Antonio breaks down material choices and cost factors.
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.
- 4
You approve before work beginsNothing starts until you say go.
Before
AfterCrawl Space Encapsulation & Vapor Barrier in San Antonio
San Antonio’s slab-on-grade construction in the military-adjacent corridors leaves thousands of homes with vented crawl spaces that pull warm, humid air upward through floor penetrations year-round. Winter Storm Uri proved how costly that thermal bypass can be when cold snaps hit. Crawl Space Encapsulation & Vapor Barrier is the full hub for this service, and in San Antonio we see the highest demand in the 1950s-70s tracts where original vapor barriers have degraded to torn plastic sheeting or nothing at all.
Crawl Space Vapor Barrier
Signs you need it
Your crawl space has standing water after rain, visible mold on floor joists, or a musty smell that rises through the floor registers.
What it costs in San Antonio
A 6-mil to 20-mil vapor barrier installation in San Antonio typically runs $1,200-$2,800 depending on crawl space square footage and existing debris.
How we do it
We remove old damaged poly, grade the soil, seam-seal new virgin polyethylene sheeting at all overlaps, and mechanically fasten to foundation walls.
Crawl Space Encapsulation
Signs you need it
Your floors are cold in winter despite running heat, humidity readings in the crawl exceed 70% RH, or you’ve had rodent nesting in insulation below.
What it costs in San Antonio
Full encapsulation with closed-cell spray foam on walls, sealed vents, and dehumidifier readiness in San Antonio generally ranges $3,500-$7,500.
How we do it
We seal all vents and penetrations, apply closed-cell foam to foundation walls, install a heavy-duty vapor barrier across the floor and up walls, and add a mechanical dehumidifier if moisture loads require it.
What Crawl Space Encapsulation & Vapor Barrier Costs in San Antonio
| Item | Typical range in San Antonio |
|---|---|
| Vapor barrier replacement (6-20 mil) | $1,200 - $2,800 |
| Full encapsulation with foam walls | $3,500 - $7,500 |
| Crawl space insulation (floor joist batts or foam) | $1,800 - $4,200 |
How long does crawl space encapsulation take in San Antonio?
Most vapor barrier jobs finish in one day; full encapsulation with foam and dehumidifier prep takes two to three days. We schedule around San Antonio’s rain patterns to avoid working in standing water.
Will encapsulation stop my floors from being cold?
Yes, sealing the crawl and adding thermal boundary at the walls or floor joists stops the convective loop that pulls cold air up. We verify with blower-door and thermal imaging before signing off.
Radiant Barrier Installation in San Antonio
San Antonio’s eight-month cooling season and 150°F+ attic temperatures make radiant barrier installation the single highest-ROI insulation upgrade in this market. The low-pitched roofs common to 1950s-70s military housing absorb massive solar gain, and without a radiant barrier that heat radiates downward into conditioned space hour after hour. Radiant Barrier Installation is our most requested summer service in neighborhoods like Converse, Leon Valley, and the southwest corridor.
Attic Radiant Barrier
Signs you need it
Your AC runs continuously after 2 p.m., attic ductwork feels hot to the touch, or your summer electric bills exceed $300 on a 1,800-square-foot home.
What it costs in San Antonio
Attic radiant barrier installation in San Antonio typically costs $1,100-$2,400 for standard gable roofs up to 2,500 square feet.
How we do it
We staple perforated aluminum foil or spray low-emissivity coating to the underside of roof decking, maintaining ventilation channels and avoiding contact with electrical.
Radiant Barrier & Ventilation
Signs you need it
Your attic has no ridge vent, soffit vents are blocked by insulation, or bathroom fans dump moist air into the cavity.
What it costs in San Antonio
Radiant barrier plus ventilation correction in San Antonio runs $1,800-$3,600 depending on current venting condition and roof complexity.
How we do it
We install baffles to preserve soffit intake, add ridge or static vents as needed, then apply radiant barrier material with proper air gap maintenance.
What Radiant Barrier Installation Costs in San Antonio
| Item | Typical range in San Antonio |
|---|---|
| Attic radiant barrier (foil or spray) | $1,100 - $2,400 |
| Radiant barrier with ventilation upgrade | $1,800 - $3,600 |
| Radiant barrier roof deck (new construction or re-roof) | $2,200 - $4,500 |
Does radiant barrier really lower electric bills in San Antonio?
Yes, in cooling-dominated climates like San Antonio’s, a properly installed radiant barrier can reduce attic heat transfer by 20-40%, which typically shows on the bill within one billing cycle.
Can radiant barrier go over existing insulation?
No, radiant barrier requires an air gap to function; we install it to the roof deck or rafters, never laid on top of attic floor insulation where it would act as a conductor.
Insulation Removal & Replacement in San Antonio
San Antonio’s military-corridor housing stock often contains original fiberglass batts compressed by sixty years of heat cycling, or worse, contamination from roof leaks and rodent activity. Winter Storm Uri drove a wave of removal jobs after burst pipes soaked attics and crawl spaces. Insulation Removal & Replacement starts with testing what we’re removing and ends with documented photos of the new, clean thermal boundary.
Contaminated Insulation Removal
Signs you need it
Your attic insulation smells musty, shows dark staining from roof leaks, or tested positive for bacteria during a home inspection.
What it costs in San Antonio
Contaminated insulation removal and disposal in San Antonio typically runs $1,500-$3,200 for a standard attic, with HEPA containment if mold is present.
How we do it
We set negative air machines, remove material in sealed bags, HEPA-vacuum all surfaces, apply antimicrobial where needed, then install new insulation to code.
Insulation Replacement
Signs you need it
Your original batts have settled below the joist tops, R-value is effectively halved, or you’re finishing an attic conversion and need current-code coverage.
What it costs in San Antonio
Insulation replacement with new blown-in or batt material in San Antonio generally costs $2,000-$4,500 for attics up to 2,000 square feet.
How we do it
We air seal first, then install new Owens Corning or Knauf fiberglass, Rockwool, or cellulose to current IECC R-values for San Antonio’s climate zone.
What Insulation Removal & Replacement Costs in San Antonio
| Item | Typical range in San Antonio |
|---|---|
| Contaminated insulation removal | $1,500 - $3,200 |
| Vermiculite or asbestos-suspect removal | $3,500 - $7,000 |
| Insulation replacement (new material only) | $2,000 - $4,500 |
Do I have to leave during insulation removal?
No, but we seal the work zone and recommend minimizing time directly below the attic hatch during active removal; HEPA filtration runs continuously.
How do I know if my old insulation is worth removing?
We photograph and sample before quoting; if it’s merely settled and clean, we often recommend adding new material over it after air sealing instead.
Attic Air Sealing in San Antonio
San Antonio’s eight-month cooling season means every cubic foot of conditioned air lost to the attic is air your AC already paid to cool. The 1950s-70s military housing stock was built with minimal attention to top plate sealing, and decades of electrical and HVAC additions have punched dozens of new holes in the ceiling plane. Attic Air Sealing is the prerequisite we complete before any insulation goes in, with blower-door numbers to prove the result.
Top Plate & Penetration Sealing
Signs you need it
You feel drafts from outlets on exterior walls, dust collects rapidly on ceiling fans, or your blower-door test shows excessive leakage at the attic floor.
What it costs in San Antonio
Top plate and penetration sealing in San Antonio typically runs $800-$1,800 for a 1,500-2,500 square foot home with standard wiring and plumbing penetrations.
How we do it
We foam-seal all top plate joints, caulk wire and pipe penetrations, and install fire-rated collars where required by San Antonio building code.
Can Light & Duct Boot Sealing
Signs you need it
Your can lights flicker when the attic gets hot, conditioned air blows from ceiling registers even when the system is off, or rooms farthest from the air handler never cool evenly.
What it costs in San Antonio
Can light sealing with fire-rated covers and duct boot mastic in San Antonio generally costs $600-$1,400 depending on fixture count and accessibility.
How we do it
We install pre-formed fire-rated enclosures over non-IC cans, seal with fire-stop caulk, and mastic-seal all flex duct connections to metal boots.
What Attic Air Sealing Costs in San Antonio
| Item | Typical range in San Antonio |
|---|---|
| Top plate and penetration sealing | $800 - $1,800 |
| Can light and duct boot sealing | $600 - $1,400 |
| Full attic air sealing (comprehensive) | $1,400 - $3,200 |
Can air sealing alone lower my electric bill?
Yes, in leaky San Antonio homes built before 1980, comprehensive attic air sealing alone can reduce cooling load by 10-20% before any insulation is added.
Do you seal before or after insulation?
Always before; we never blow insulation over an unsealed attic floor, because once the material is in place you cannot access the leaks underneath.
Wall Insulation in San Antonio
San Antonio’s wall insulation challenge is bifurcated: the limestone block and hollow clay tile homes of Monte Vista, King William, and Beacon Hill have no cavities to fill, while the post-WWII wood-frame belt in military corridors often has empty stud bays or degraded R-11 batts. Wall Insulation requires different approaches for each construction type, and we quote only after confirming what the walls actually contain.
Injection Foam Wall Insulation
Signs you need it
Your wood-frame home has no insulation in exterior walls, rooms with exterior walls are noticeably hotter in summer, or you’re replacing siding and want one-shot access.
What it costs in San Antonio
Injection foam wall insulation for a 2,000-square-foot wood-frame home in San Antonio typically runs $3,500-$6,500 depending on wall height and obstructions.
How we do it
We drill 5/8-inch holes at stud bay intervals, inject slow-rise foam from the interior or exterior depending on finish conditions, then patch and match texture.
Drill & Fill Wall Insulation
Signs you need it
Your 1960s-70s tract home has empty stud bays confirmed by thermal imaging, or previous blown-in settled and left gaps at the top and bottom plates.
What it costs in San Antonio
Drill and fill with dense-pack cellulose or fiberglass in San Antonio generally costs $2,800-$5,200 for standard 8-foot walls on a 1,800-square-foot home.
How we do it
We drill access holes, dense-pack cellulose or fiberglass to 3.5 pounds per cubic foot to prevent settling, then plug holes with matching material.
What Wall Insulation Costs in San Antonio
| Item | Typical range in San Antonio |
|---|---|
| Injection foam (wood-frame walls) | $3,500 - $6,500 |
| Drill and fill (dense-pack cellulose/fiberglass) | $2,800 - $5,200 |
| Interior rigid foam (limestone/clay tile retrofit) | $8,500 - $15,000 |
Can you insulate limestone block walls from outside?
No, exterior insulation on historic limestone or clay tile requires interior application; we install rigid foam board and re-drywall, which is a significant scope that we explain fully before quoting.
Is wall insulation worth it if my attic is already done?
In San Antonio’s cooling-dominated climate, attic work yields higher ROI first, but wall insulation matters for rooms with west-facing exposure where solar gain dominates; we prioritize by thermal imaging results.
Attic Cleaning & Rodent Proofing in San Antonio
San Antonio’s warm climate and mature tree canopy create year-round rodent pressure, and the 1950s-70s housing stock has decades of roof penetrations, vent gaps, and eave returns that mice and rats exploit. Contaminated attic insulation is a health hazard, not merely an efficiency problem. Attic Cleaning & Rodent Proofing removes the contamination and seals the entry paths so it does not recur.
Attic Sanitizing & Decontamination
Signs you need it
You’ve found droppings in the attic, smelled ammonia from urine, or had an HVAC contractor flag biological contamination in return air pathways.
What it costs in San Antonio
Attic sanitizing and decontamination in San Antonio typically runs $1,200-$2,800 depending on contamination extent and square footage.
How we do it
We remove soiled insulation, HEPA-vacuum all surfaces, apply enzyme-based sanitizer, and install new insulation only after clearance testing.
Rodent Proofing & Exclusion
Signs you need it
You hear scratching at night, find gnawed wiring, or have had repeated pest control treatments that never address how rodents enter the structure.
What it costs in San Antonio
Rodent proofing and exclusion for a typical San Antonio home runs $900-$2,200 depending on roof complexity and number of entry points identified.
How we do it
We inspect with motion-activated cameras if needed, seal all entry points 1/4-inch or larger with rodent-proof materials, and install vent guards and chimney caps.
What Attic Cleaning & Rodent Proofing Costs in San Antonio
| Item | Typical range in San Antonio |
|---|---|
| Attic sanitizing and decontamination | $1,200 - $2,800 |
| Rodent proofing and exclusion | $900 - $2,200 |
| Full attic restoration (cleanout, sanitize, re-insulate) | $3,500 - $7,500 |
Will rodents come back after you seal?
Not through the same entries; our exclusion work carries the 365-Day Done Right Promise, and we document every sealed point with photos.
Do you remove dead rodents from the attic?
Yes, removal is part of sanitizing scope; we locate and extract carcasses, then treat the area with odor-neutralizing enzyme before re-insulating.
Home Energy Audit in San Antonio
A home energy audit in San Antonio identifies where your conditioned air escapes and whether your insulation performs to its labeled R-value in actual field conditions. The 1950s-70s military housing stock typically tests far leakier than owners expect, and newer north-side builds often have spray foam gaps or thermal bridging that code inspection missed. Home Energy Audit provides the diagnostic foundation for every insulation decision we recommend.
Blower Door Test
Signs you need it
Your home feels drafty despite closed windows, rooms vary by more than 5°F from the thermostat, or you’re considering insulation but don’t know where to start.
What it costs in San Antonio
A standalone blower-door test in San Antonio typically costs $250-$450; we credit this toward any work we perform.
How we do it
We install a calibrated fan in an exterior door, depressurize the house to 50 Pascals, and measure CFM50 to quantify total envelope leakage.
Thermal Imaging Inspection
Signs you need it
You suspect missing insulation in walls, have had ice damming or moisture staining, or want to verify spray foam coverage after a previous contractor’s work.
What it costs in San Antonio
Thermal imaging included with a full audit in San Antonio runs $350-$600; standalone imaging starts at $300.
How we do it
We scan with FLIR infrared cameras during blower-door depressurization to make air leaks visible, then mark findings on floor plans for repair prioritization.
What Home Energy Audit Costs in San Antonio
| Item | Typical range in San Antonio |
|---|---|
| Blower-door test (standalone) | $250 - $450 |
| Full home energy audit with thermal imaging | $350 - $600 |
| Duct leakage test (included or add-on) | $200 - $350 |
How long does a home energy audit take?
A full audit with blower-door and thermal imaging takes two to three hours for a typical San Antonio home; you receive a written report with photos and prioritized recommendations within 48 hours.
Will the audit tell me exactly what to fix first?
Yes, we rank findings by cost-effectiveness and safety; in San Antonio’s climate, attic air sealing and radiant barrier almost always top the list for pre-1980 homes.
Brands We Service in San Antonio
We stock and install Owens Corning, Johns Manville, Knauf, Rockwool, CertainTeed, Icynene, Demilec, and GreenFiber products, selected by application rather than pushed as proprietary solutions. Our San Antonio office carries common batt and blown-in sizes for same-day starts, with specialty foam and rigid board ordered to job specifications. Our brands page lists full technical data sheets.
Pricing for Insulation in San Antonio, TX
| Service | Typical range in San Antonio |
|---|---|
| Crawl space vapor barrier | $1,200 - $2,800 |
| Crawl space encapsulation | $3,500 - $7,500 |
| Attic radiant barrier | $1,100 - $2,400 |
| Radiant barrier with ventilation | $1,800 - $3,600 |
| Contaminated insulation removal | $1,500 - $3,200 |
| Insulation replacement | $2,000 - $4,500 |
| Attic air sealing (comprehensive) | $1,400 - $3,200 |
| Injection foam wall insulation | $3,500 - $6,500 |
| Drill and fill wall insulation | $2,800 - $5,200 |
| Attic sanitizing and decontamination | $1,200 - $2,800 |
| Rodent proofing and exclusion | $900 - $2,200 |
| Full home energy audit | $350 - $600 |
Prices in San Antonio push higher for homes with active roof leaks requiring dry-out, limited attic access hatches that need enlargement, or pre-1940s masonry construction requiring interior retrofit work. Every job still begins with a written price before any work starts, per Haven Standard Clause 1.
Neighborhoods We Serve in San Antonio
Our crews work across the full San Antonio metro, from the historic core to the expanding north and northeast corridors. Most San Antonio addresses receive same-day or next-day scheduling confirmation.
- King William / Lavaca
- Monte Vista / Beacon Hill
- Stone Oak / Hardy Oak
- Helotes / Grey Forest
- Converse / Live Oak
Service Area - Cities Near San Antonio
We dispatch from our San Antonio office to surrounding communities including Converse, TX, Universal City, TX, Schertz, TX, and Cibolo, TX. The same crew, same written price, same documented photo record applies in every service area.
Serving San Antonio, TX - Our Local Coverage Area
We’re based in the San Antonio 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 About Insulation in San Antonio
Attic insulation replacement typically does not require a permit in San Antonio, but spray foam, wall insulation, and crawl space encapsulation may trigger building department review depending on scope. We handle permit applications as part of our written scope when required, at no additional markup.
Most San Antonio homeowners receive a same-day or next-day appointment for estimates, with work starting within three to five business days for standard attic and radiant barrier jobs. Emergency water-damage removals move to front of queue.
Yes, we regularly work in Monte Vista, King William, and other historic neighborhoods; we provide the product data sheets and photo documentation that San Antonio historic review boards and HOAs typically require for exterior-visible work.
Ready to see what your home actually needs? Call (830) 420-0953 for a free estimate. We’ll send a written price before any work starts, and you’ll get a documented photo record when the crew leaves.
What happens when you call
- 1A real person answersNo phone trees - talk to a local insulation pro.
- 2You get an upfront price rangeHonest numbers before anyone is dispatched. No surprises.
- 3A background-checked tech heads outLicensed & insured, typically same-day.
- 4You approve before work beginsNothing starts until you say go.
What San Antonio Customers Say
"They air-sealed the attic floor before insulating and showed me the blower-door number before and after. The upstairs is finally the same temperature as downstairs."
- Marisol D."Crawl space encapsulation done properly. Photographs of the vapour barrier at every seam, and the damp smell in the hallway is gone."
- Ainsley P."Two other companies quoted to blow more insulation on top of what was there. These were the only ones who said the existing material had to come out first, and explained why."
- Clifford E.