Insulation in San Antonio, TX
Crawl space encapsulation and vapor barrier installation in San Antonio typically runs $3,500-$8,500 for a full encapsulation, with vapor barrier-only jobs starting around $1,800-$3,200. Most San Antonio homes built during the 1970s-1990s boom inside Loop 1604 sit on slab foundations, but the pier-and-beam pockets in neighborhoods like King William, Lavaca, and Monte Vista face chronic moisture intrusion from Gulf humidity swings and clay soils that shift seasonally. At Envelope Insulation Co., we start every crawl space job with air sealing and moisture control before adding any insulation - sealed first, then insulated, in that order. Call (830) 243-6352 for a written price before any work starts.
Why San Antonio Homes Are Different
San Antonio sits in IECC Climate Zone 2A, which means cooling dominates the energy budget - attic temperatures regularly hit 140-150°F in summer, baking ductwork and forcing HVAC systems to work overtime. The city’s housing stock is overwhelmingly slab-on-grade tract construction from the 1970s-1990s inside Loop 410 and Loop 1604, built to Texas energy codes requiring as little as R-11 attic insulation. That’s catastrophically undersized for this heat load.
The February 2021 Winter Storm Uri exposed how thin these thermal envelopes are on the heating side too, spiking demand for air sealing and insulation upgrades that had been deferred for decades. CPS Energy runs targeted rebate programs for attic insulation upgrades that no neighboring city’s utility replicates, making retrofit conversations both urgent and financially specific to San Antonio. Older inner-city neighborhoods like King William and Monte Vista contain pier-and-beam homes where floor insulation and rim joist sealing are often absent or deteriorated. And because so many local homes have ducted HVAC sitting in unconditioned attics, the “conditioned attic” approach - spray foam to the roof deck - has become a de facto market standard here, far more common than in cooler Texas metros.
Our Main San Antonio Services
San Antonio homeowners call us most often for attic work and spray foam - here is what those jobs look like locally.
Attic Insulation in San Antonio
Most San Antonio attics we inspect inside Loop 1604 hold R-11 to R-19 fiberglass batts installed during original construction, well below the R-38 to R-60 recommended for Climate Zone 2A. We remove the existing material, seal top plates and penetrations, then install blown-in fiberglass or cellulose to the proper depth. On every applicable job, we run a blower-door test - a pressurization reading that shows, in one number, how much air the building envelope was losing before and after. Attic Insulation in San Antonio
Spray Foam Insulation in San Antonio
The conditioned attic approach is especially common here: open-cell spray foam applied directly to the roof deck keeps ducts inside the thermal envelope and can cut cooling bills by 20-30%. We source materials from Owens Corning, Johns Manville, and other manufacturers - no proprietary lock-in - and publish before-and-after blower-door numbers so you can verify the air-sealing result. Every job starts with a written price and ends with a Documented Photo Record. Spray Foam Insulation in San Antonio
Blown-In Insulation in San Antonio
Blown-in fiberglass or cellulose is the most cost-effective way to bring a 1980s tract home up to modern R-value without removing the existing attic floor. We air seal first - top plates, can lights, duct boots - then blow to depth, typically 14-18 inches for R-38 to R-49. The work takes one day for most homes under 2,500 square feet, and CPS Energy rebates often apply. 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.
Before
AfterCrawl Space Encapsulation & Vapor Barrier in San Antonio
San Antonio’s pier-and-beam homes in King William, Lavaca, and Monte Vista face a specific moisture problem: Gulf humidity swings create hot-dry-to-humid cycles that stress vapor management, while clay soils shift seasonally, opening gaps at rim joists and foundation vents. Crawl Space Encapsulation & Vapor Barrier jobs here require vapor management before insulation goes in, or the new material traps moisture against floor joists and breeds mold.
Crawl Space Vapor Barrier
Signs you need it
Musty odors rising through floor registers, soft spots in hardwood floors, or visible condensation on joists during humid mornings in Monte Vista or Lavaca homes signal that ground moisture is migrating upward unchecked.
What it costs in San Antonio
A 6-mil to 20-mil vapor barrier installed over bare earth in a typical San Antonio crawl space runs $1,800-$3,200, with thicker reinforced barriers at the higher end.
How we do it
We remove debris, grade the soil for drainage, seam-seal a reinforced polyethylene sheet to foundation walls, and seal all penetrations before any insulation touches the joists.
Crawl Space Encapsulation
Signs you need it
Standing water after rain, pest activity in insulation, or HVAC ducts sweating in the crawl space indicate the full envelope - walls, floor, and vents - needs sealing.
What it costs in San Antonio
Full encapsulation with closed-cell foam on walls, vapor barrier on floor, sealed vents, and a dehumidifier typically ranges $3,500-$8,500 for San Antonio homes under 2,500 square feet.
How we do it
We seal foundation vents, apply closed-cell spray foam to walls, install the vapor barrier with sealed seams, add a condensate-pumped dehumidifier, and verify humidity levels below 60% before signing off.
What Crawl Space Encapsulation & Vapor Barrier Costs in San Antonio
| Item | Typical range in San Antonio |
|---|---|
| Vapor barrier (6-20 mil, floor only) | $1,800 - $3,200 |
| Full encapsulation with dehumidifier | $3,500 - $8,500 |
| Crawl space insulation (after encapsulation) | $1,500 - $3,500 |
Does crawl space encapsulation help with summer humidity in San Antonio?
Yes - encapsulation blocks the 70-80% relative humidity common in San Antonio crawl spaces during summer, protecting floor joists and reducing the load on your HVAC system. Call (830) 243-6352 for a written price on your specific crawl space.
Can you encapsulate a crawl space with foundation venting requirements?
San Antonio’s building code allows sealed crawl spaces when mechanical ventilation or dehumidification is provided; we document the compliance path in your written scope before work begins.
Radiant Barrier Installation in San Antonio
San Antonio attic temperatures regularly hit 140-150°F, and the 1970s-1990s tract homes inside Loop 1604 were built with dark shingle roofs and minimal insulation, creating a radiant heat load that forces air conditioners to cycle continuously. Radiant Barrier Installation reflects that infrared energy back toward the roof deck rather than letting it penetrate to the attic floor, reducing attic temperatures by 20-30°F and cutting cooling runtime measurably.
Attic Radiant Barrier
Signs you need it
Your upstairs rooms stay hot past 10 p.m., your AC runs nonstop from June through September, or your ductwork in the attic feels hot to the touch - all point to excessive radiant gain.
What it costs in San Antonio
Radiant barrier foil stapled to rafters or laid over existing attic insulation in a typical San Antonio home runs $1,200-$2,800.
How we do it
We air seal the attic floor first, then install perforated radiant barrier foil with proper drape for ventilation channels, avoiding compression that would reduce its reflective performance.
Radiant Barrier Roof Deck
Signs you need it
During a re-roof or new construction in Alamo Heights or Terrell Hills, applying radiant barrier directly to the roof deck prevents the attic from becoming a solar oven in the first place.
What it costs in San Antonio
Radiant barrier roof deck application during roofing or new construction typically adds $1,500-$3,500 to the project, depending on roof pitch and accessibility.
How we do it
We apply radiant barrier sheathing or foil directly to the roof deck before shingles go on, ensuring the reflective surface faces the attic air space with adequate venting above.
What Radiant Barrier Installation Costs in San Antonio
| Item | Typical range in San Antonio |
|---|---|
| Attic radiant barrier (foil, existing home) | $1,200 - $2,800 |
| Radiant barrier roof deck (new construction/re-roof) | $1,500 - $3,500 |
| Radiant barrier with attic air sealing package | $2,200 - $4,500 |
Does radiant barrier work with existing attic insulation?
Yes - radiant barrier complements rather than replaces insulation; we lay it over existing fiberglass or cellulose after air sealing, and the combined system performs better than either alone. Call (830) 243-6352 for a written price.
Will radiant barrier help my ducts in the attic?
Reducing attic temperature from 150°F to 120°F lowers the temperature differential across your ductwork, meaning less cooled air is lost before it reaches your registers.
Insulation Removal & Replacement in San Antonio
San Antonio’s housing boom decades left thousands of attics with R-11 fiberglass batts that have settled, compressed, or been compromised by roof leaks, rodent activity, or the humid conditions that follow Gulf moisture intrusion. Insulation Removal & Replacement is common in homes where the existing material cannot be salvaged or where contaminants make it a health risk.
Attic Insulation Removal
Signs you need it
Insulation is compressed below its original thickness, shows water staining from past roof leaks, or has been disturbed by rodents - all make it ineffective and potentially hazardous.
What it costs in San Antonio
Removal of existing attic insulation in a typical 1,800-2,500 square foot San Antonio home runs $1,000-$2,500, depending on access and contamination level.
How we do it
We use commercial vacuums with HEPA filtration to remove old material without spreading fibers through the house, bag it for proper disposal, and inspect the deck for leaks or damage before anything new goes in.
Contaminated Insulation Removal
Signs you need it
Strong ammonia odors, visible droppings, or mold growth on insulation indicate biological contamination that requires full removal and sanitizing before replacement.
What it costs in San Antonio
Contaminated insulation removal with decontamination and sanitizing typically ranges $2,500-$5,500 in San Antonio, with severe cases requiring more extensive cleanout.
How we do it
We remove all compromised material, apply antimicrobial treatment to affected surfaces, verify dryness with moisture meters, and document the clean deck with photos before installing new insulation.
What Insulation Removal & Replacement Costs in San Antonio
| Item | Typical range in San Antonio |
|---|---|
| Standard attic insulation removal | $1,000 - $2,500 |
| Contaminated insulation removal + decon | $2,500 - $5,500 |
| Removal + replacement with new R-38 to R-49 | $3,500 - $7,500 |
Can you remove insulation without tearing out my ceiling?
Yes - we remove attic insulation from above through the attic hatch or access point; your ceiling drywall stays intact throughout the process. Call (830) 243-6352 for a written price.
How do I know if my old insulation is contaminated?
Musty smells, visible discoloration, or pest evidence are clear indicators; we inspect and photograph the condition before quoting removal, so you see what we see.
Attic Air Sealing in San Antonio
The 1970s-1990s tract homes that dominate San Antonio’s market were built with minimal attention to airtightness - top plates, electrical penetrations, and can lights leak conditioned air directly into 140°F attics. Attic Air Sealing is the single most cost-effective upgrade for these homes, and we treat it as a hard prerequisite before adding any insulation.
Attic Floor Air Sealing
Signs you need it
Dust streaks around ceiling registers, rooms that never reach set temperature, or a blower-door reading above 3,500 CFM50 in a home under 2,500 square feet indicate excessive attic bypass leakage.
What it costs in San Antonio
Comprehensive attic floor air sealing in a typical San Antonio home runs $1,500-$3,500, with larger or more complex attics toward the higher end.
How we do it
We seal all top plate joints, electrical and plumbing penetrations, and framing gaps with fire-rated caulk and foam, then verify the reduction with a blower-door test before insulation goes in.
Can Light & Duct Boot Sealing
Signs you need it
Hot attic air pouring through can lights when the AC is off, or visible gaps where flex duct meets ceiling registers, show direct paths for conditioned air loss.
What it costs in San Antonio
Sealing can lights with approved covers and mastic-sealing duct boots typically adds $800-$2,000 to an attic air sealing package in San Antonio.
How we do it
We install fire-rated airtight covers over non-IC can lights, seal duct boots with mastic and mesh, and pressure-test the duct system where accessible to confirm no post-seal leaks.
What Attic Air Sealing Costs in San Antonio
| Item | Typical range in San Antonio |
|---|---|
| Attic floor air sealing (comprehensive) | $1,500 - $3,500 |
| Can light and duct boot sealing | $800 - $2,000 |
| Full air sealing + blower-door verification | $2,200 - $4,500 |
Is air sealing worth it before adding insulation?
Absolutely - blowing new insulation over an unsealed attic floor is like pouring water into a bucket with holes; we seal first, then insulate, and publish the before-and-after blower-door numbers to prove the difference. Call (830) 243-6352 for a written price.
How much does air sealing lower my bills?
Most San Antonio homeowners see 10-20% cooling bill reduction from attic air sealing alone, with greater savings when combined with proper insulation levels.
Wall Insulation in San Antonio
San Antonio’s slab-on-grade tract homes from the 1970s-1990s were built with 2×4 exterior walls and minimal or no cavity insulation, while older pier-and-beam homes in King William and Monte Vista often have empty wall cavities or deteriorated rock wool. Wall Insulation retrofits here require techniques that don’t require full gut renovation.
Injection Foam Wall Insulation
Signs you need it
Walls that radiate heat in summer, cold spots near exterior walls in winter, or high cooling bills despite good attic insulation suggest empty or underfilled wall cavities.
What it costs in San Antonio
Injection foam insulation for exterior walls in a typical 1,800 square foot San Antonio home runs $3,500-$7,500, depending on wall area and access.
How we do it
We drill 2-inch holes at stud spacing, inject slow-rise foam that fills without bowing drywall, patch and texture-match the holes, and verify fill with thermal imaging.
Drill & Fill Wall Insulation
Signs you need it
Knocking on exterior walls produces a hollow sound, or original construction records show no insulation in 2×4 walls - common in Alamo Ranch and Helotes area homes from the 1980s.
What it costs in San Antonio
Drill-and-fill with dense-pack cellulose in a typical San Antonio home runs $2,500-$5,500, with textured or stucco exteriors adding labor for patching.
How we do it
We remove a row of siding or drill through stucco, blow cellulose to density with continuous-fill tubes, patch the access points to match existing finish, and confirm density with wall cavity pressure readings.
What Wall Insulation Costs in San Antonio
| Item | Typical range in San Antonio |
|---|---|
| Injection foam (exterior walls) | $3,500 - $7,500 |
| Drill-and-fill cellulose | $2,500 - $5,500 |
| Interior wall soundproofing | $1,800 - $4,000 |
Can you insulate walls without removing drywall?
Yes - injection foam and dense-pack cellulose both fill cavities through small exterior or interior access points, with patching that blends into existing texture. Call (830) 243-6352 for a written price.
Does wall insulation help with outside noise?
Dense-fill cellulose and certain foams reduce exterior noise transmission by 5-10 decibels, noticeable on busy streets like Broadway or near Loop 410.
Attic Cleaning & Rodent Proofing in San Antonio
San Antonio’s warm climate and mature tree canopy create ideal conditions for roof rats and squirrels, which commonly access attics through construction gaps in 1970s-1990s tract homes and older pier-and-beam properties in Monte Vista and King William. Attic Cleaning & Rodent Proofing addresses both the pest entry and the contamination they leave behind.
Attic Cleanout
Signs you need it
Scurrying sounds at dusk, shredded insulation, or acorn caches in attic corners indicate active rodent presence that requires removal and cleaning before any new work.
What it costs in San Antonio
Attic cleanout with debris removal and surface sanitizing in a typical San Antonio home runs $1,200-$3,000, with heavy contamination or limited access toward the higher end.
How we do it
We remove all contaminated insulation and debris, HEPA-vacuum the deck, apply enzymatic sanitizer, and photograph the clean space before quoting any replacement work.
Rodent Proofing & Exclusion
Signs you need it
Recurring pest problems after trapping, visible gnaw marks on fascia boards, or gaps larger than 1/4 inch at roof junctions and vent screens show entry points that trapping alone won’t fix.
What it costs in San Antonio
Comprehensive rodent proofing with metal flashing, hardware cloth, and sealant for a typical San Antonio home runs $1,500-$3,500, with multi-story or steep roofs adding labor.
How we do it
We inspect every roof penetration, vent, and construction gap with the homeowner present, seal with rodent-proof materials, install chimney and vent guards, and guarantee the work for one year with documented photos.
What Attic Cleaning & Rodent Proofing Costs in San Antonio
| Item | Typical range in San Antonio |
|---|---|
| Attic cleanout + sanitizing | $1,200 - $3,000 |
| Rodent proofing & exclusion | $1,500 - $3,500 |
| Cleanout + proofing + insulation replacement | $4,000 - $9,000 |
How do I know if rodents are in my attic right now?
Fresh droppings, urine staining on insulation, or nighttime activity sounds are definitive; we inspect and photograph evidence during our initial visit. Call (830) 243-6352 for a written price.
Can you clean and re-insulate the same attic?
Yes - we sequence cleanout, proofing, and reinsulation as a single project with one written price and warranty, so you’re not coordinating multiple contractors.
Home Energy Audit in San Antonio
San Antonio homeowners facing $400+ summer electric bills often don’t know whether the problem is insulation, duct leakage, HVAC sizing, or all three - and CPS Energy rebates require documentation that guesswork can’t provide. Home Energy Audit gives you a prioritized, measured roadmap with blower-door and duct-blaster numbers that qualify for utility incentives.
Blower Door Test
Signs you need it
You’ve upgraded your HVAC but bills stayed high, or you’re applying for CPS Energy rebates that require pre- and post-improvement airtightness documentation.
What it costs in San Antonio
A standalone blower-door test with written report in San Antonio runs $300-$600, with package discounts when bundled with improvement work.
How we do it
We depressurize the house to 50 Pascals, measure CFM50 leakage, use smoke pencils to locate major bypasses, and deliver a written report with prioritized air sealing targets.
Thermal Imaging Inspection
Signs you need it
Uneven temperatures room-to-room, ice dam history before Uri, or suspicion of missing wall insulation in a 1980s tract home all show clearly with infrared imaging.
What it costs in San Antonio
Thermal imaging added to a blower-door audit or performed separately runs $250-$500 for a typical San Antonio home, with full written documentation.
How we do it
We scan every exterior wall, ceiling, and foundation junction with a FLIR camera during controlled conditions, mark thermal anomalies on photos, and correlate findings with blower-door data to distinguish air leakage from missing insulation.
What Home Energy Audit Costs in San Antonio
| Item | Typical range in San Antonio |
|---|---|
| Blower-door test with written report | $300 - $600 |
| Thermal imaging inspection | $250 - $500 |
| Comprehensive audit (blower door + thermal + duct test) | $500 - $1,200 |
Does CPS Energy accept your audit for rebates?
Yes - our audits meet CPS Energy’s documentation requirements for insulation and air sealing rebates; we provide the completed forms with your report. Call (830) 243-6352 to schedule.
How long does a full energy audit take?
Plan on 2.5 to 4 hours for a comprehensive audit; we test, image, and review findings with you on site so you leave with actionable information, not a wait for a report.
Brands We Service in San Antonio
We source insulation and air sealing materials from Owens Corning, Johns Manville, Knauf, and Rockwool - no proprietary product lock-in means we specify what’s right for your home, not what’s in our warehouse. Most materials are stocked locally for next-day starts on approved jobs. our brands
Pricing for Insulation in San Antonio, TX
| Service | Typical range in San Antonio |
|---|---|
| Crawl space vapor barrier | $1,800 - $3,200 |
| Full crawl space encapsulation | $3,500 - $8,500 |
| Attic radiant barrier | $1,200 - $2,800 |
| Radiant barrier roof deck | $1,500 - $3,500 |
| Attic insulation removal | $1,000 - $2,500 |
| Contaminated insulation removal | $2,500 - $5,500 |
| Attic air sealing | $1,500 - $3,500 |
| Injection foam wall insulation | $3,500 - $7,500 |
| Drill-and-fill wall insulation | $2,500 - $5,500 |
| Attic cleanout + sanitizing | $1,200 - $3,000 |
| Rodent proofing & exclusion | $1,500 - $3,500 |
| Home energy audit (comprehensive) | $500 - $1,200 |
Prices in San Antonio push higher when attic access is limited, roof pitch is steep, or existing contamination requires hazmat handling. Under Haven Standard Clause 1, every job begins with a flat written price, written scope, and written warranty before anyone lifts a tool - no exceptions.
Neighborhoods We Serve in San Antonio
Our crews work across San Antonio from the central core to the outer loops, with dispatch coordinated from our San Antonio office. Most appointments are scheduled within 48 hours, with same-day availability for urgent situations.
- Alamo Heights
- King William
- Monte Vista
- Terrell Hills
- Stone Oak
Service Area - Cities Near San Antonio
We serve homeowners throughout the San Antonio metro, including Converse, TX, Universal City, TX, Schertz, TX, and Cibolo, TX. Scheduling and dispatch are coordinated from our San Antonio office, with crews assigned to minimize drive time to your location.
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 retrofits don’t require permits in San Antonio, but spray foam applied to roof decks and any structural modification do; we verify permit requirements in your written scope before work begins and handle the application when needed.
A live person answers our line 24/7, and we typically schedule inspections within 24-48 hours across San Antonio; same-day service is available for urgent situations like post-storm water intrusion or HVAC failure related to attic conditions.
Yes - our attic insulation and air sealing work meets CPS Energy rebate program requirements, and we provide the documentation you need to file; the rebate amount varies by improvement type and is paid directly by CPS Energy after verification.
Call (830) 243-6352 today for a free estimate with a written price before any work starts. Under The Haven Standard, you’ll get a named technician, a text when they’re on the way, and a Documented Photo Record when the job is done. If it’s not done right, we make it right - that’s the 365-Day Done Right Promise.
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."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."The winter gas bill dropped by about a third. They had estimated a quarter, so they under-promised."
- Genevieve R.