Johns Manville Home Energy Audit in San Antonio: What to Know First
A Johns Manville home energy audit in San Antonio typically costs between $199 and $450 depending on home size and the number of tests you want run, and most audits take two to three hours from start to finish. We’re an independent Johns Manville service provider, which means we work on homes with Johns Manville batt insulation, blown-in fiberglass, and spray foam systems every week. The audit tells you exactly where your house is leaking air, where your insulation has settled or failed, and what it’ll cost to fix it properly for this climate.
If you own a San Antonio home built with Johns Manville products and your electric bill keeps climbing every summer, this page is for you. Call (866) 751-4428 and we’ll walk you through what an audit covers and whether it’s the right first step for your house.
How Johns Manville Products Fail - and How We Find It
After 25 years in San Antonio attics, we know exactly what goes wrong with Johns Manville products in this heat. Here’s what we regularly uncover during a home energy audit:
- JM Formaldehyde-Free Fiberglass Batts (R-13 and R-19): The kraft paper facing breaks down in San Antonio attic heat after 15 to 20 years, letting the batt sag away from the drywall. This creates a gap between the insulation and the ceiling below it, which means your air-conditioned air escapes into the attic. In houses near Alamo Heights and Terrell Hills, we find this within the first 20 minutes of nearly every audit. The fix is usually attic air sealing followed by blown-in insulation over the top.
- Johns Manville Attic Protector Blown-In Fiberglass: This stuff settles in our humidity. We measure settled depth with a calibrated ruler, and in homes across Stone Oak and Cibolo, we often find R-38 installed 15 years ago has compacted down to R-25 or less. The manufacturer’s coverage chart assumes ideal conditions, but a San Antonio attic with 150-degree summer temperatures and moisture swings doesn’t match those assumptions. That’s a real-world number you won’t find on JM’s product sheet.
- JM Corbond III Closed-Cell Spray Foam: When installed correctly, Corbond III performs well here, but we see a recurring problem in San Antonio homes where the foam was sprayed too thin at the roof deck. The foam pulls away from the decking as the wood expands and contracts with our temperature swings, creating hairline gaps that leak conditioned air. An infrared scan picks these up in minutes. JM’s own literature won’t tell you that, because it’s an installation issue, not a manufacturing defect.
- Johns Manville MR Faced Batts in Crawl Spaces: Homes with pier-and-beam foundations, especially around Monte Vista and Alamo Heights, often have JM MR faced batts stapled under the floor joists. Rodents love nesting in this material, and once they tear the facing, the insulation drops. During an audit, we check crawl space insulation integrity with a camera before we ever run the blower door. A torn crawl space insulation system can account for 10 percent of a home’s total energy loss and most owners have no idea.
- JM Spider Custom Insulation (Spray-In Fiberglass): Spider works fine at the time of installation, but in San Antonio’s humidity, we see it hold moisture against wall cavities more than JM’s own technical data suggests. That trapped moisture slowly degrades the fiberglass structure and creates a musty smell inside walls, especially in bathrooms and laundry rooms. A thermal imaging inspection shows the temperature difference that tells us Spider has absorbed moisture and stopped doing its job.
Each of these failures shows up differently in an audit, which is why we don’t do a quick walk-through and call it done. We measure, we scan, and we document.
Our Johns Manville Home Energy Audit Process
Here’s what happens when you call us for a home energy audit on a San Antonio house with Johns Manville insulation:
- 1
The call. You reach a live person, not a voicemail. We ask about your home’s age, the insulation type you know about, and what’s bugging you most: high bills, hot rooms, or drafts.
- 2
Visual inspection. We walk the attic, crawl space, and exterior. We note what Johns Manville product is installed, where it’s failing, and take photos so you can see it yourself.
- 3
Blower door test. We pressurize the house and measure total air leakage. This gives us a number, not a guess. Most San Antonio homes from the 1990s and 2000s test between 2,500 and 4,000 CFM50. A tight house should be under 1,500.
- 4
Thermal imaging. Infrared cameras show us exactly where heat is entering and cooled air is escaping, including gaps behind walls that no one can see with the naked eye.
- 5
Duct leakage test. We pressurize your ductwork separately. In San Antonio, we regularly find 15 to 30 percent of conditioned air leaking into attics before it ever reaches a room register.
- 6
A written report and an honest recommendation. We tell you what’s worth fixing now, what can wait, and what the cost will be. No scare tactics, no upsell.
If the fix is insulation replacement or air sealing, we’ll quote it on the spot and schedule it. If it’s something outside our scope, we’ll say that too.
What Johns Manville Home Energy Audit Costs in San Antonio
Here’s what you should expect to pay for a home energy audit in the San Antonio area, based on the jobs we do most often:
- Blower door test only: $150 to $250
- Standard full audit (blower door + thermal imaging + visual inspection): $199 to $349 for homes under 2,500 square feet
- Full audit with duct leakage test (recommended for homes over 20 years old): $299 to $449
- Attic-only inspection with thermal imaging: $99 to $199
What moves the price is home size, number of systems, and whether you want duct testing included. The good news: we don’t charge a trip fee inside our service county, and if you already have a written estimate from another company for insulation work, we’ll give you a free second opinion. Call (866) 751-4428 for an exact quote on your house.
Why San Antonio Homeowners Call Walt’s Insulation for Johns Manville Work
We’re the one down the road, not a call center in another state. Walt Brenner grew up on the north side of San Antonio, learned the trade at San Antonio College, and started Walt’s Insulation in 2000 because he was tired of watching homeowners get sold insulation that couldn’t handle South Texas heat. We answer the phone live, 24/7, and every tech who walks into your home is background-checked and uniformed. Our Done Right Promise covers the workmanship for life. If we install insulation or air sealing and it’s not done right, we come back and make it right. No fine print, no runaround. We also work with Reflectix radiant barrier and other brands including Owens Corning, Rockwool, and CertainTeed, so if your Johns Manville product isn’t the only thing in your attic, we can handle the whole job in one visit.
FAQs
No. A home energy audit is a diagnostic process that doesn’t alter or modify your Johns Manville products in any way. We do not cut, remove, or change the insulation during an audit, so your JM product warranty remains fully intact. If the audit finds a manufacturer defect, we’ll document it so you can file a warranty claim with Johns Manville directly.
A full audit with blower door testing and thermal imaging takes two to three hours for most homes under 3,000 square feet. Homes with multiple HVAC systems or hard-to-access crawl spaces can take up to four hours. We schedule audits Monday through Saturday, and same-week appointments are usually available.
It depends on what the audit finds. If your JM batt insulation is still in good condition and the problem is air leaks around penetrations, attic air sealing costs $800 to $1,800 and is far cheaper than replacement. But if the insulation has settled, been rodent-damaged, or held moisture, replacement with new blown-in fiberglass typically runs $2,500 to $6,500 for a standard San Antonio attic. We’ll show you the photos and the test numbers so you can decide with real information, not a sales pitch.
In most cases, yes. We keep same-day and next-day audit slots open because San Antonio heat doesn’t wait. Call (866) 751-4428 and we’ll tell you within five minutes when we can be there.
We find what our equipment finds. The blower door gives us a hard number for air leakage, the thermal camera shows temperature differences that indicate failed insulation, and our crawl space inspections catch damage most companies never look for because they don’t want to get dirty. You’ll see every finding in the report we leave with you, not in a follow-up email three days later.
Written by Walt Brenner, Owner, Walt’s Insulation at Walt’s Insulation, serving San Antonio and nearby areas.