Insulation in San Antonio, TX
Crawl space encapsulation and vapor barrier installation in San Antonio typically runs $3,500-$7,500 for a standard ranch home, with most jobs completed in two days. The city’s 1950s-1970s slab-on-grade housing stock sits directly on clay soils that wick moisture upward year-round, making ground vapor the single most overlooked source of indoor humidity and energy loss. We’re Envelope Insulation Co., and we treat air sealing as a hard prerequisite before any insulation goes in - every job starts with a written price and ends with a documented record. Call (830) 529-7780 for a free estimate.
Why San Antonio Homes Are Different
San Antonio sits in IECC Climate Zone 2, the hottest residential building-code zone in the country, where attic temperatures hit 150-160°F in July and August. That heat load makes insulation the dominant lever on CPS Energy bills, not a minor efficiency tweak.
The core housing stock is slab-on-grade brick-veneer ranch homes built from roughly 1950-1980 to house workers at Lackland AFB, Randolph AFB, and Fort Sam Houston. Original attic insulation is typically compressed fiberglass batts at R-11 or less with virtually no air sealing at top plates. In older inner-city neighborhoods like Monte Vista and Beacon Hill, early-1900s balloon-frame and Craftsman homes have hollow walls and heavily degraded attic coverage.
The semi-arid climate means radiant heat gain dominates over humidity, so radiant barriers and air-impermeable spray foam deliver outsized returns compared to Houston or Dallas. Occasional sharp winter cold fronts, the “blue northers” that drop 40°F in hours, expose every attic air-sealing gap that summer never reveals. CPS Energy’s rebate program for attic insulation R-value upgrades and air sealing documentation rewards contractors who know the paperwork; we bundle that incentive into every qualifying proposal.
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 peak attic temperatures on homes that were built to R-11 or less. We start with a blower-door test to measure conditioned air loss, seal top plates and penetrations, then install Owens Corning or Johns Manville products to the appropriate R-value for Zone 2. Every job gets before-and-after pressurization numbers so you can verify the result. Attic Insulation in San Antonio
Spray Foam Insulation in San Antonio
Spray foam insulation in San Antonio creates the air-impermeable barrier that semi-arid, high-radiant climates demand. We specify open-cell or closed-cell Icynene and Demilec products based on whether the application is attic roof deck, crawl space, or wall cavity, and we never spray over unsealed surfaces. The blower-door test confirms the air-sealing performance before we close the job. Spray Foam Insulation in San Antonio
Blown-In Insulation in San Antonio
Blown-in insulation in San Antonio is our most common retrofit for 1960s-1970s ranch homes with settled or compressed attic batts. We use GreenFiber cellulose or Knauf fiberglass, blown to uniform depth after air sealing is complete - never before. The material fills irregular joist bays and covers top plates that batts always miss. Blown-In Insulation in San Antonio
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.
Crawl Space Encapsulation & Vapor Barrier in San Antonio
San Antonio’s slab-on-grade ranch homes from the 1950s-1970s were built with minimal ground separation, and the clay soils beneath them wick moisture upward continuously. A crawl space encapsulation and vapor barrier system stops that vapor drive before it reaches your floor framing, your indoor air, and your energy bill. Crawl Space Encapsulation & Vapor Barrier is the first step we recommend for any home with a vented crawl space in Bexar County.
In the Hill Country fringe neighborhoods like Helotes and Alamo Ranch, where limestone outcroppings create drainage complications, we see more standing water and mold-compromised joists than in the flat clay plains closer to downtown. The work is different depending on what we find, but the sequence never changes: remove debris and contaminated material, seal the ground and walls, then condition the space.
Crawl Space Vapor Barrier
Signs you need it
Your floors feel cold in winter despite the heat running, or you smell mustiness that worsens after rain.
What it costs in San Antonio
A 6-mil to 20-mil vapor barrier installation for a standard San Antonio crawl space typically runs $1,200-$2,800 depending on square footage and seam-sealing requirements.
How we do it
We remove debris, lay and seam-seal polyethylene sheeting across the entire ground surface, seal it to foundation walls, and install mechanical fasteners at perimeter edges.
Crawl Space Encapsulation
Signs you need it
You see standing water after storms, mold on floor joists, or insulation falling from the subfloor saturated with moisture.
What it costs in San Antonio
Full crawl space encapsulation in San Antonio, including wall liners, sealed vents, and dehumidification, typically ranges from $3,500-$7,500 for a ranch home under 2,000 square feet.
How we do it
We install reinforced polyethylene wall and ground liners, seal all vents and penetrations, add a condensate-pumped dehumidifier, and provide a written humidity target with monitoring instructions.
What Crawl Space Encapsulation & Vapor Barrier Costs in San Antonio
| Item | Typical range in San Antonio |
|---|---|
| Vapor barrier (ground only) | $1,200 - $2,800 |
| Full encapsulation with dehumidifier | $3,500 - $7,500 |
| Encapsulation with insulation replacement | $5,500 - $10,000 |
Does crawl space encapsulation help with summer cooling bills in San Antonio?
Yes - by blocking ground vapor and reducing the latent load your air conditioner must remove, encapsulation typically drops cooling runtime 10-15% in Zone 2 homes with vented crawl spaces. Call (830) 529-7780 and we’ll measure your current humidity levels during the free estimate.
How long does crawl space encapsulation take in San Antonio?
Most standard ranch-home encapsulations are completed in two to three days; larger homes or those requiring joist repair extend to four days. We deliver a written schedule with the price before anyone starts.
Radiant Barrier Installation in San Antonio
San Antonio’s Climate Zone 2 designation means more annual cooling degree days than Dallas or Houston, and the semi-arid conditions let radiant heat dominate attic loads in ways that humid climates don’t. A radiant barrier installation reflects that roof-deck heat before it radiates into your insulation and down through your ceiling, making it one of the highest-ROI envelope improvements in Bexar County. Radiant Barrier Installation is particularly effective on 1960s-1980s ranch homes where the attic ductwork was never designed for 150°F ambient temperatures.
We install radiant barriers only after air sealing is complete - blowing in insulation over an unsealed attic is something we won’t do. The Haven Standard requires it.
Attic Radiant Barrier
Signs you need it
Your upstairs rooms stay hot past 10 p.m., your ductwork sits in the attic, or your summer CPS Energy bills spike despite the AC never cycling off.
What it costs in San Antonio
Attic radiant barrier installation in San Antonio typically runs $1,500-$3,200 for a standard ranch home, depending on roof pitch and accessibility.
How we do it
We staple perforated radiant barrier foil across bottom chords of roof trusses, maintaining ventilation channels, after completing attic floor air sealing and blower-door verification.
Radiant Barrier Roof Deck
Signs you need it
You’re replacing your roof and want the radiant barrier integrated at the deck level rather than retrofitting foil later.
What it costs in San Antonio
Radiant barrier roof deck application during reroofing in San Antonio typically adds $2,000-$4,500 to the roofing scope, depending on square footage and sheathing replacement needs.
How we do it
We apply radiant barrier sheathing or foil-faced decking during roof replacement, sealed at seams, with documented photos of the installation before shingles go on.
What Radiant Barrier Installation Costs in San Antonio
| Item | Typical range in San Antonio |
|---|---|
| Attic radiant barrier (foil retrofit) | $1,500 - $3,200 |
| Radiant barrier roof deck (with reroof) | $2,000 - $4,500 |
| Radiant barrier with attic air sealing package | $2,800 - $5,500 |
Does radiant barrier work with existing attic insulation in San Antonio?
Yes - radiant barrier complements rather than replaces insulation, and we install it after air sealing but before adding blown-in or batt insulation to the attic floor. Call (830) 529-7780 for a free assessment of your current R-value and radiant barrier potential.
How much can radiant barrier lower my CPS Energy bill?
Most San Antonio homeowners see attic heat gain reductions of 20-35% after proper radiant barrier installation, with corresponding cooling-load decreases that vary by home size and duct location.
Insulation Removal & Replacement in San Antonio
San Antonio’s 1950s-1980s housing stock contains decades of compressed, contaminated, or improperly installed insulation that performs well below its labeled R-value. Insulation removal and replacement is the only way to correct prior work that skipped air sealing, used the wrong material, or left rodent debris and moisture damage in place. Insulation Removal & Replacement jobs in Alamo Heights and Terrell Hills often reveal multiple material eras layered on top of each other with no sealing at any point.
We document everything we remove with photos, bag it for proper disposal, and provide a written scope for what goes back in - sealed first, then insulated, every time.
Contaminated Insulation Removal
Signs you need it
You see droppings, urine staining, or mold on existing insulation, or you smell ammonia or mustiness that enters the living space through recessed lights.
What it costs in San Antonio
Contaminated insulation removal in San Antonio typically runs $2,000-$4,500 depending on attic square footage, contamination extent, and whether hazmat protocols apply.
How we do it
We set up negative air pressure, remove and bag contaminated material, HEPA-vacuum all surfaces, apply antimicrobial treatment where appropriate, and provide photos of the clean substrate before new insulation goes in.
Insulation Replacement
Signs you need it
Your insulation is compressed below joist height, has settled unevenly, or was installed before 1990 without an air barrier.
What it costs in San Antonio
Insulation replacement with new blown-in or batt material in San Antonio typically ranges from $2,500-$5,500 for a standard attic, including air sealing.
How we do it
We remove old material, seal all top plates and penetrations verified by blower-door test, then install new Knauf or Owens Corning insulation to specified depth with uniform coverage documentation.
What Insulation Removal & Replacement Costs in San Antonio
| Item | Typical range in San Antonio |
|---|---|
| Contaminated insulation removal only | $2,000 - $4,500 |
| Standard insulation replacement with air sealing | $2,500 - $5,500 |
| Full removal, cleaning, and replacement | $4,500 - $9,000 |
Do I have to leave my house during insulation removal in San Antonio?
No - we isolate the work zone with containment and negative pressure, though we recommend sensitive individuals spend the day elsewhere as a precaution. Call (830) 529-7780 to discuss scheduling around your household’s needs.
How do I know if my old insulation contains asbestos?
Vermiculite insulation and pre-1990 duct wrap are the most common asbestos-containing materials we encounter in San Antonio; we test suspect materials before disturbing them and use licensed abatement contractors when required.
Attic Air Sealing in San Antonio
San Antonio’s 1950s-1980s ranch homes were built with virtually no air sealing at top plates, can lights, or duct boots - the “ventilated attic” theory of the era assumed air leakage was harmless. Attic air sealing stops the conditioned air you’re paying to cool from escaping into 150°F attic space, and it’s the single most cost-effective envelope improvement for most Bexar County homes. Attic Air Sealing is mandatory before we install any insulation; we will not blow insulation over an unsealed attic floor.
The blue northers that sweep through in winter find every gap that summer’s smaller temperature differential missed, which is why we pressurize homes during sealing work regardless of season.
Top Plate & Penetration Sealing
Signs you need it
Your blower-door test shows excessive air leakage, or you feel drafts at exterior wall outlets and baseboards during winter cold fronts.
What it costs in San Antonio
Top plate and penetration sealing in San Antonio typically runs $1,800-$3,500 for a standard ranch home, depending on framing complexity and access.
How we do it
We access top plates by moving existing insulation, apply expanding foam or caulk to all plate-to-drywall gaps, seal wire and pipe penetrations, and verify with a second blower-door test.
Can Light & Duct Boot Sealing
Signs you need it
You see dirty insulation around recessed lights or duct boots, indicating air is being pulled through those gaps every time the system runs.
What it costs in San Antonio
Can light and duct boot sealing in San Antonio typically ranges from $800-$2,200 depending on fixture count and whether airtight replacement housings are needed.
How we do it
We seal accessible boots with mastic and mesh, install fire-rated airtight covers over non-IC can lights, and verify duct connections with pressure pan testing.
What Attic Air Sealing Costs in San Antonio
| Item | Typical range in San Antonio |
|---|---|
| Top plate and penetration sealing | $1,800 - $3,500 |
| Can light and duct boot sealing | $800 - $2,200 |
| Full attic air sealing package | $2,500 - $5,000 |
Can attic air sealing alone lower my CPS Energy bill?
Yes - a 30-50% reduction in air leakage typically cuts cooling and heating costs 15-25% before any insulation is added, because your conditioned air stays where it belongs. Call (830) 529-7780 for a blower-door test and written leakage target.
Do you need to remove my insulation to seal the attic?
We move existing insulation to access top plates and penetrations, then replace it uniformly; if the insulation is contaminated or compressed, we recommend removal and replacement as part of the same scope.
Wall Insulation in San Antonio
San Antonio’s early-1900s balloon-frame homes in Monte Vista and Beacon Hill were built without wall cavities meant for insulation, while 1950s-1970s ranch homes often have empty 2×4 walls that meet no modern thermal standard. Wall insulation is the only way to address the 25-35% of heat loss that moves through walls in these homes, and it’s particularly critical in Climate Zone 2 where the cooling load never truly rests. Wall Insulation in San Antonio requires methods that don’t require gutting finished interiors.
We use injection foam and drill-and-fill techniques that leave minimal repair work, and we always verify with thermal imaging that the cavity is fully filled with no voids.
Injection Foam Wall Insulation
Signs you need it
Your exterior walls are hot to the touch in summer, your rooms have large temperature swings between interior and exterior walls, or your home was built before 1980 with empty stud cavities.
What it costs in San Antonio
Injection foam wall insulation in San Antonio typically runs $3,500-$7,000 for a 1,500-square-foot home, depending on wall area and cavity condition.
How we do it
We drill 5/8-inch holes at stud spacing, inject slow-rise foam to fill each cavity completely, patch and texture-match the holes, and verify fill with thermal imaging from the interior.
Drill & Fill Wall Insulation
Signs you need it
You want fiberglass or cellulose rather than foam, or your walls have obstructions that make foam injection impractical.
What it costs in San Antonio
Drill-and-fill fiberglass or cellulose wall insulation in San Antonio typically ranges from $2,500-$5,500 for a standard home, with GreenFiber cellulose as our most common specification.
How we do it
We drill access holes, blow in dense-packed cellulose or fiberglass to specified density, patch and finish the holes, and confirm no settling with follow-up thermal imaging.
What Wall Insulation Costs in San Antonio
| Item | Typical range in San Antonio |
|---|---|
| Injection foam wall insulation | $3,500 - $7,000 |
| Drill-and-fill cellulose or fiberglass | $2,500 - $5,500 |
| Exterior wall insulation with interior finish repair | $5,000 - $10,000 |
Will wall insulation make my house quieter in San Antonio?
Dense-packed wall insulation reduces airborne sound transmission 5-10 decibels, which is noticeable for street noise in urban neighborhoods like Tobin Hill or Five Points. Call (830) 529-7780 and we’ll discuss acoustic versus thermal priorities for your walls.
Can you insulate walls without removing drywall?
Yes - injection foam and drill-and-fill methods require only small access holes that we patch and texture-match, making them practical for finished homes without renovation.
Attic Cleaning & Rodent Proofing in San Antonio
San Antonio’s mature tree canopy and established neighborhoods create ideal rodent highway systems, and the 1950s-1980s ranch homes with minimal air sealing offer easy attic access through soffit gaps and roofline penetrations. Attic cleaning and rodent proofing removes contaminated material, sanitizes the space, and seals entry points so the problem doesn’t recur - because new insulation installed over rodent debris is wasted money. Attic Cleaning & Rodent Proofing is often the first step before we can air seal and insulate properly.
We see heavy rodent activity in homes near greenbelts and the San Antonio River corridor, where roof rats travel tree-to-tree and find construction gaps that builders never sealed.
Rodent Proofing & Exclusion
Signs you need it
You hear scratching at night, find droppings in the attic, or see gnaw marks on fascia boards and soffit vents.
What it costs in San Antonio
Rodent proofing and exclusion in San Antonio typically runs $1,500-$3,500 depending on entry point count, roof complexity, and whether one-way doors are needed for active eviction.
How we do it
We inspect the roofline and foundation, seal all entry points larger than 1/4 inch with rodent-proof materials, install one-way doors where active infestation exists, and provide a written exclusion map with photo documentation.
Attic Sanitizing & Decontamination
Signs you need it
You smell ammonia or mustiness from the attic, see urine-stained insulation, or have had rodents removed and need the space safe for new insulation.
What it costs in San Antonio
Attic sanitizing and decontamination in San Antonio typically ranges from $2,000-$4,500 depending on square footage, contamination level, and whether insulation removal is included.
How we do it
We remove contaminated material, HEPA-vacuum all surfaces, apply enzyme-based sanitizer to break down organic waste, and provide photos of the clean substrate before any new work begins.
What Attic Cleaning & Rodent Proofing Costs in San Antonio
| Item | Typical range in San Antonio |
|---|---|
| Rodent proofing and exclusion | $1,500 - $3,500 |
| Attic sanitizing and decontamination | $2,000 - $4,500 |
| Full attic cleanout, proofing, and insulation replacement | $5,000 - $10,000 |
How do I know rodents are gone before you insulate?
We verify exclusion with a two-week monitoring period using one-way doors and interior traps, and we inspect for new activity before any insulation work begins. Call (830) 529-7780 to schedule an inspection and written exclusion plan.
Does homeowners insurance cover rodent damage in San Antonio?
Most policies exclude rodent damage as a maintenance issue, though some cover secondary damage like chewed wiring if it causes a fire; we document everything with photos to support any claim you choose to file.
Home Energy Audit in San Antonio
A home energy audit in San Antonio quantifies exactly where your conditioned air is escaping and which envelope improvements will deliver the highest return in Climate Zone 2’s extreme cooling load. The audit is particularly valuable for 1950s-1980s ranch homes with unknown construction history, where the combination of minimal original insulation and decades of owner modifications creates unpredictable thermal performance. Home Energy Audit results from Envelope Insulation Co. include a written priority list with estimated savings and CPS Energy rebate eligibility.
We perform audits before recommending any work, and we use the results to write a scope that targets the biggest leaks first - no guesswork, no selling insulation where air sealing is the actual problem.
Blower Door Test
Signs you need it
Your energy bills are higher than comparable homes, you feel drafts you can’t locate, or you’re considering insulation and want to know your actual leakage rate first.
What it costs in San Antonio
A standalone blower-door test in San Antonio typically runs $350-$600, or it’s included at no charge when bundled with a written scope for follow-up work.
How we do it
We install a calibrated fan in an exterior door, depressurize the house to 50 Pascals, measure CFM50 leakage, and use smoke pencils and infrared cameras to locate the dominant leak paths.
Thermal Imaging Inspection
Signs you need it
You have uneven temperatures between rooms, suspect missing insulation, or want to verify wall-cavity fill after injection foam installation.
What it costs in San Antonio
Thermal imaging inspection in San Antonio typically ranges from $250-$500 as a standalone service, or it’s included in our comprehensive audit package.
How we do it
We scan all building surfaces with a FLIR camera during controlled temperature differential conditions, mark thermal anomalies on photos, and correlate findings with the blower-door leakage data.
What Home Energy Audit Costs in San Antonio
| Item | Typical range in San Antonio |
|---|---|
| Blower-door test (standalone) | $350 - $600 |
| Thermal imaging inspection | $250 - $500 |
| Comprehensive home energy audit | $500 - $900 |
Does a home energy audit qualify for CPS Energy rebates in San Antonio?
Yes - CPS Energy’s rebate program requires pre- and post-work documentation including blower-door numbers, which our audit provides in the format their program accepts. Call (830) 529-7780 and we’ll bundle rebate paperwork into your proposal.
How long does a home energy audit take?
A comprehensive audit including blower-door test, thermal imaging, and duct leakage testing takes three to four hours for a standard San Antonio home, with the written report delivered within 48 hours.
Brands We Service in San Antonio
We specify and install Owens Corning, Johns Manville, Knauf, and GreenFiber products based on what each job requires - no proprietary lock-in, no brand upsell. Our San Antonio office stocks common batts, blown-in, and air-sealing materials for same-day starts on standard jobs. our brands
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 | $1,500 - $3,200 |
| Radiant barrier roof deck | $2,000 - $4,500 |
| Contaminated insulation removal | $2,000 - $4,500 |
| Insulation replacement | $2,500 - $5,500 |
| Attic air sealing (full package) | $2,500 - $5,000 |
| Injection foam wall insulation | $3,500 - $7,000 |
| Drill-and-fill wall insulation | $2,500 - $5,500 |
| Rodent proofing and exclusion | $1,500 - $3,500 |
| Attic sanitizing and decontamination | $2,000 - $4,500 |
| Comprehensive home energy audit | $500 - $900 |
Prices in San Antonio increase with attic square footage over 2,500 square feet, steep roof pitches above 6:12, and homes requiring extensive deck repair or electrical relocation before insulation can be installed. Every job begins with a written price - no work starts without it - under Haven Standard Clause 1.
Neighborhoods We Serve in San Antonio
Our crews work throughout Bexar County and surrounding areas, with dispatch coordinated from our San Antonio office. Most neighborhoods receive same-day or next-day response for estimates.
- Monte Vista
- Beacon Hill
- Alamo Heights
- Terrell Hills
- Tobin Hill
- Five Points
- Helotes
- Alamo Ranch
Service Area - Cities Near San Antonio
We serve homeowners throughout the San Antonio metro area and in surrounding communities including Converse, TX, Universal City, TX, Schertz, TX, and Helotes, TX. Scheduling and dispatch are coordinated from our San Antonio office, with crews assigned by proximity to keep response times short.
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
Most attic insulation and air sealing work in San Antonio does not require a permit, but spray foam applications and any electrical modifications during the job may trigger a building department review; we handle permit research and submission as part of our written scope when required.
We answer calls with a live person 24/7, and most San Antonio estimates are scheduled within 24-48 hours; emergency situations like failed insulation after a roof leak are prioritized same-day when possible. Call (830) 529-7780 to check current availability.
Some San Antonio HOAs, particularly in master-planned communities like Alamo Ranch or Stone Oak, have architectural review requirements for exterior modifications; we provide the product data sheets and installation specifications your HOA needs for approval before work begins.
Ready to see what your home is actually losing? Call (830) 529-7780 for a free estimate with a written price before any work starts. Every job gets a Documented Photo Record, and on applicable work we provide before-and-after blower-door numbers so you can verify the air-sealing result yourself. The 365-Day Done Right Promise applies to all completed work - if it’s not done right, we make it right.
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 within the hour.
- 4You approve before work beginsNothing starts until you say go.
What San Antonio Customers Say
"The winter gas bill dropped by about a third. They had estimated a quarter, so they under-promised."
- Genevieve R."They photographed rodent damage in the old insulation that we had no idea about, and priced the exclusion work separately so we could decide."
- Harriet N."Crawl space encapsulation done properly. Photographs of the vapour barrier at every seam, and the damp smell in the hallway is gone."
- Ainsley P.