Trusted Blown-In Insulation for San Antonio Homeowners
Blown-in insulation in San Antonio typically costs $1,500 to $3,800 for a full attic installation depending on square footage and material choice, with most jobs completed in a single day. For comparison, see our Blown-In Insulation pricing breakdowns. Walt’s Insulation has handled blown-in insulation work across Bexar County since 2000, from Alamo Heights to Stone Oak to Helotes, and we answer our phones live around the clock. If your attic insulation has settled, your upstairs rooms bake in August, or your energy bills climb every summer, call (866) 751-4428 and we’ll give you a straight answer, not a sales pitch.
The heat here isn’t like other places. San Antonio summers run long and mean, with 100-degree days stretching from June into September. Houston Blown-In Insulation customers tell us the same thing: blown-in insulation is often the single biggest lever a homeowner can pull to make those months bearable. Loose-fill material settles into every corner, joist bay, and odd-shaped cavity in ways batts simply can’t. We’ve crawled through thousands of San Antonio attics and seen the same story over and over: bare spots over bedrooms, thin coverage near the eaves, and HVAC ducts sweating through under-insulated spaces. That’s what we fix.
Walt’s Insulation is locally owned and owner-operated, founded by Walt Brenner in 2000. Walt Brenner built this company on a simple idea: do the job right the first time and stand behind it forever. That’s the Done Right Promise, and it’s been our rule for over 25 years. No franchises, no call centers. When you call, a live person picks up. When we come out, a background-checked, uniformed technician walks your attic. When the job’s done, it’s done right or we make it right.
What Our Blown-In Insulation Service Includes
Blown-in insulation isn’t one-size-fits-all. The right material and method depend on your home’s age, framing, existing insulation, and where the heat is coming from. Here’s what we do and when each option makes sense.
Blown-In Cellulose
Blown-in cellulose is ground-up recycled paper treated with borate for fire resistance and pest deterrence. It settles into dense, even coverage and performs especially well in older San Antonio homes with irregular joist spacing or lots of cross-bracing where batts would leave gaps. We typically install GreenFiber cellulose, blowing it to the depth needed to hit your target R-value, usually R-38 to R-60 for attics in our climate zone. Cellulose also does a better job of blocking airflow through small cracks than fiberglass, which matters in houses built before modern air-sealing standards.
Blown-In Fiberglass
Blown-in fiberglass consists of tiny glass fibers that create millions of air pockets for thermal resistance. It won’t settle as much as cellulose over time, won’t absorb moisture, and is a good choice for homes where weight or humidity is a concern. We work with CertainTeed fiberglass products and know their coverage charts by heart. The material goes in fluffy and stays that way, maintaining its R-value as long as the attic isn’t disturbed.
Dense-Pack Wall Insulation
Dense-pack wall insulation is blown-in material compressed into closed wall cavities at high pressure. It’s the go-to solution for older San Antonio homes with empty wall cavities, balloon framing, or original construction that predates modern insulation codes. We drill small access holes, fill the cavity completely, and patch everything to match. The result is a wall that finally holds heat in winter and keeps it out in summer, something countless homes in neighborhoods like Monte Vista and Tobin Hill desperately need. We also provide Blown-In Insulation in Pasadena for homes facing similar challenges.
Blown-In Top-Up
A top-up means blowing additional insulation over what’s already in your attic to bring the total depth up to modern standards. If your existing insulation is in decent shape but measures only 4 to 6 inches deep, you’re running maybe R-13 to R-19 when you should have R-49 or better. We inspect what’s there, check for moisture or pest damage first, and then blow fresh material on top to reach the depth your home needs. It’s faster and cheaper than a full removal, and in many San Antonio homes it’s all that’s required.
Every one of these methods comes with the same Walt’s Insulation standards: upfront pricing before we start, uniformed technicians who show up on time, and the lifetime Done Right Promise covering our workmanship.
What happens when you call
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A real person answersNo phone trees - you reach a local pro.
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You get an upfront price rangeHonest numbers before anyone is dispatched.
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A background-checked tech heads outLicensed & insured, dispatched right away.
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You approve before work beginsNothing starts until you say go.
Brands We Service for Blown-In Insulation
We install blown-in insulation from manufacturers we trust, because the material matters as much as the hand spreading it. GreenFiber cellulose has been our go-to for years: it’s consistent, it’s treated with borate, and we know exactly how it behaves when blown into hot San Antonio attics. Their coverage charts are accurate, which means you get the R-value you paid for, not a guess.
CertainTeed fiberglass is another product line we work with regularly. It’s manufactured to the same spec batch after batch, and we’ve installed enough of it to predict exactly how any given job will go. We also have experience with Demilec and Icynene products when a job calls for spray-applied insulation solutions. Whether you have existing GreenFiber, CertainTeed, or any other blown-in product in your attic, we can top it up, remove it, or replace it. The brand on the bag matters less than the person running the blower.
Signs You Need Blown-In Insulation Right Now
Most San Antonio homeowners don’t think about insulation until something forces them to. These are the warning signs we hear about most often.
- Upstairs rooms are 10 degrees hotter than downstairs. Heat rises, and when your attic insulation is thin or settled, that heat keeps going right into the rooms below. This is the most common complaint we hear in two-story homes across San Antonio, and it’s almost always an insulation problem, not an HVAC problem.
- Your air conditioner runs constantly and never satisfies the thermostat. An AC that can’t keep up in July is often working against a roof that’s radiating heat through an under-insulated attic. Companies all over San Antonio sell bigger AC units, but the honest fix is often more insulation. We’ll tell you which one you need, and won’t sell you a new unit if you don’t.
- Your insulation has settled to 4 inches or less. Cellulose and fiberglass both settle over time, especially older fiberglass batts that get compressed by roofers or cable installers. If your insulation doesn’t reach the top of your joists, you’re losing comfort and money every single month.
- You can see the tops of your ceiling joists. When joists are visible, you have at most R-11 to R-19 up there. San Antonio homes need R-49 to R-60. That’s roughly three to five times what you have. A blown-in top-up closes that gap in an afternoon.
- Your energy bills keep climbing even though your usage hasn’t changed. Attic insulation degrades slowly, and utility rates climb at the same time. Together, they mask each other. If your summer bills feel like they’ve doubled over five years, your attic is likely part of the problem.
If any of these sound familiar, call (866) 751-4428. We’ll arrange an inspection and give you an honest assessment of what’s going on up there. Estimates are free and come with a free second opinion on any written quote you’ve gotten from another contractor.
Our Blown-In Insulation Process - Step by Step
Here’s exactly what happens when you hire Walt’s Insulation for blown-in insulation in San Antonio. No mystery, no surprises.
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The attic inspection. A uniformed technician walks your attic and takes real measurements: current insulation depth, joist spacing, ventilation, recessed light clearances, and any sign of moisture, rodent activity, or wiring issues. We photograph everything so you can see exactly what we see. This inspection is free inside our service county.
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The honest recommendation. We tell you what you need, what you don’t need, and what each option costs before any work begins. If a top-up will get you to R-49 at half the price of a full removal, we’ll say so. If your existing insulation has water damage or rodent contamination, we’ll recommend removal and explain why.
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Prep work and air sealing. Before insulation goes in, we address the air leaks that let conditioned air escape through your ceiling: plumbing penetrations, electrical boxes, can light gaps, and the attic hatch. Air sealing makes the insulation do its job. Skipping it is the difference between a job that works and a job that looks good but performs poorly.
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The blow-in installation. We run hoses from the truck to the attic, set depth markers on the joists, and blow material to the exact depth your target R-value requires. For dense-pack walls, we drill, fill, and patch. For top-ups, we layer fresh material over the top. Every job gets a final depth check with a ruler, not a guess.
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Cleanup and verification. We remove our equipment, seal any wall penetrations we made, and walk you through what was done. You get before and after photos, plus a written record of the R-value achieved. And because every job carries the Done Right Promise, if anything isn’t right, we come back and fix it. No runaround, no fine print.
How Much Does Blown-In Insulation Cost in San Antonio?
A full blown-in attic insulation job in San Antonio typically runs $1,500 to $3,800 for an average 1,500 to 2,500 square foot home. A blown-in top-up over existing insulation usually lands between $800 and $1,800. Dense-pack wall insulation is more involved, generally running $2,500 to $6,000 depending on how many walls and how much access work is required. These are honest ranges based on the jobs we’ve done across Bexar County, not teaser numbers designed to get a foot in the door.
What affects the price? Square footage, target R-value, whether old insulation needs removal first, accessibility of the attic, and whether air sealing is included. A cramped attic with a low roof pitch takes longer than a wide-open space. Pest contamination or moisture damage adds remediation time. Material choice matters too: fiberglass and cellulose are comparably priced, but premium options and higher R-values shift the number up. The best way to avoid overpaying is to get a written line-item estimate and insist on knowing exactly what depth and R-value you’re getting. We give that to every customer before any work begins. And remember: seniors and veterans save 10%, always. No trip charge inside the service county, and we’ll happily provide a free second opinion on any other written estimate you’ve received.
Blown-In Insulation Near San Antonio - Our Service Area
Walt’s Insulation is based right here in San Antonio and serves the entire Bexar County metro area, including Alamo Heights, Terrell Hills, Castle Hills, Leon Valley, Converse, Schertz, Cibolo, Universal City, Helotes, and Boerne. We also regularly work with homeowners throughout south central Texas. Most insulation jobs can be scheduled within a few days, and for urgent situations we’ll get a crew out fast. If you’re outside the city limits, call us and ask, we’re likely close by. And if you still have questions, take a look at our home page to see how we work. Our other Texas locations serve Blown-In Insulation in Houston, Blown-In Insulation in Spring, and Blown-In Insulation in The Woodlands.
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.
Frequently Asked Questions - Blown-In Insulation in San Antonio
Blown-in insulation is loose-fill material, either cellulose or fiberglass, installed by blowing it into attics or wall cavities using a mechanical blower. It fills gaps and settles around framing far better than batt insulation can, making it ideal for San Antonio attics with irregular joist spacing. We install both fiberglass and cellulose depending on the home and the goal.
A typical San Antonio attic takes one day from setup to cleanup. Dense-pack wall jobs take longer, usually one to two days depending on how many walls and how much drilling is required. We’ll give you a firm timeline before we start so you know exactly what to expect.
A full blown-in attic job costs $1,500 to $3,800 on average, top-ups run $800 to $1,800, and dense-pack walls range $2,500 to $6,000. Your exact price depends on square footage, R-value target, material, and whether removal is needed first. Call (866) 751-4428 for a free estimate with a written line-item quote, plus a free second opinion on any other estimate you’ve received.
We install and work with GreenFiber, CertainTeed, Demilec, Icynene, and other major manufacturers. If your attic has an older or lesser-known product, we can still top it up, remove it, or replace it. The brand matters less than the installer’s attention to depth, coverage, and air sealing.
If a tree limb has punched through your ceiling, a rodent has torn through your insulation, or a remodel exposed an empty wall cavity, call (866) 751-4428. Our phones are answered by a live person 24/7, and for genuine emergencies we’ll get someone out as fast as logistics allow. You’ll never reach a voicemail.
All Walt’s Insulation work is covered by the lifetime Done Right Promise. If our workmanship isn’t done right, we make it right, no runaround and no expiration date. The only thing we can’t guarantee is someone else’s work, which is why we stand behind every job we do with our name on it.
Clear a path to the attic access, move any valuables away from walls if we’re doing dense-pack work, and secure pets in a comfortable room. We’ll handle everything else: floor protection inside, attic safety equipment, and full cleanup after the job. Most homeowners don’t need to do anything beyond letting us in.
Schedule Your Blown-In Insulation Service in San Antonio Today
Your attic isn’t going to insulate itself, and another San Antonio summer is coming. Call Walt’s Insulation at (866) 751-4428 for a free, no-obligation estimate. We’ll inspect your attic, give you an honest recommendation, and quote a price you won’t have to second-guess. No trip charge in the service county, 10% off for seniors and veterans, and a real person answers the phone, day or night. That’s how we’ve done it since 2000, and how we’ll do it for you.
Written by Walt Brenner, Owner at Walt’s Insulation, serving San Antonio since 2000.