Trusted Blown-In Insulation for Seguin Homeowners
Blown-In Insulation in Seguin typically runs $1,200-$3,800 for most attics, and we can usually get your job scheduled within 48 hours. We don’t blow anything in until we’ve sealed the leaks first - that’s the Haven Standard we’ve operated under since 2016. Call (830) 549-6646 and a live person will pick up, 24/7.
Seguin’s combination of hot, humid summers and occasional hard freezes puts real stress on under-insulated homes. We’ve sealed and insulated over 9,000 homes since 2016, and the pattern we see in Guadalupe County is consistent: builders in the 2005-2015 boom years often installed the minimum R-30 in attics, which drops to R-20 or lower once settling and gaps take their toll. The result is rooms that won’t cool below 78 degrees in August, ice dams on north-facing eaves in January, and energy bills that climb 20-40% above what a properly sealed and insulated envelope should cost. Our crews work throughout Seguin proper and the surrounding communities, from the older homes near Walnut Springs to newer builds in Mill Creek Crossing and the subdivisions along Highway 46.
Every job starts with a written price before any work starts - Haven Standard Clause 1 - and ends with a Documented Photo Record. On jobs where air sealing is part of the scope, you’ll also receive before-and-after blower-door numbers showing exactly how much conditioned air your home was losing before and after. No voicemail loops, no callback windows measured in business days. Just a flat price, a written scope, and a crew that shows up when promised.
What Our Blown-In Insulation Service Includes
Blown-In Cellulose
Cellulose is ground paper fiber treated with borate fire retardant, and it’s the material we reach for most often in Seguin attics because it performs well in our humidity when installed at proper density. We typically install it at R-38 to R-60 depending on your ceiling joist depth and whether we’re working over existing insulation or starting fresh. In Seguin’s climate, cellulose has an advantage: it manages moisture cycles better than fiberglass when attic ventilation is marginal, which is common in the 1980s-2000s ranch homes you’ll find throughout the city. We source cellulose from GreenFiber and other manufacturers, and we never blow it over an unsealed attic floor - top plates, can lights, plumbing and electrical penetrations get sealed first with foam and caulk. The blower-door test after sealing tells us whether we’ve done that part right before any insulation goes in.
Blown-In Fiberglass
Fiberglass loose-fill is exactly what it sounds like - glass fibers blown through a hose to achieve a uniform thermal blanket. It’s lighter than cellulose, which matters when you’re adding R-value over existing insulation that may already be near the joist tops. We use Owens Corning AttiCat and similar systems for fiberglass jobs, and we pay close attention to coverage uniformity because fiberglass that settles unevenly creates thermal bypasses that show up as hot spots on infrared cameras. In Seguin, we see fiberglass specified most often for new construction top-offs and for homeowners who want the non-combustible properties fiberglass offers. Like every blown-in job we do, it gets the same air-sealing prerequisite - no exceptions. The written scope you receive before work starts specifies exactly which areas get sealed and with what materials.
Dense-Pack Wall Insulation
Dense-pack is blown-in insulation installed into closed wall cavities at a density high enough to resist settling - typically 3.5 pounds per cubic foot for cellulose, slightly higher for fiberglass. This is the service for Seguin homeowners with uninsulated or under-insulated exterior walls, which is nearly every home built before 1975 and many built through the early 1990s. We access wall cavities through exterior siding (removed and replaced), interior drywall (patched and repainted), or from the attic by dropping tubes down stud bays - the method depends on your siding type, interior finish, and whether we’re working around existing insulation. In Seguin’s historic districts and the older neighborhoods near St. Joseph Catholic Church, we’ve dense-packed walls in homes with original clapboard, asbestos shingle, and early Hardie board. The key measurement is the fill density: too loose and the insulation settles in six months, too tight and you bow studs or crack drywall. We document the installed density in our photo record so you have proof of proper installation.
Blown-In Top-Up
A top-up adds loose-fill insulation over existing material to restore or increase R-value where settling, compression, or removal has reduced performance. This is the most common blown-in service we perform in Seguin because so many attics start with adequate insulation that degrades over 10-15 years. Before we top up, we inspect what’s there - wet or moldy insulation comes out, pest-damaged material gets removed, and we air seal the attic floor as if it were a new installation. The blown-in insulation in Seguin jobs we’ve completed in subdivisions like Oak Creek and River Oaks often start as top-ups after homeowners notice their summer cooling bills spiking. We measure existing depth with a ruled probe, calculate the current R-value based on material type and compression, then specify exactly how much new material is needed to reach your target. The written price includes the material, the labor, the air sealing, and the blower-door verification if applicable.
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 source blown-in insulation materials from Owens Corning, GreenFiber, Johns Manville, Knauf, Rockwool, CertainTeed, Icynene, and Demilec - no proprietary product lock-in means we specify what performs best for your specific application rather than what a manufacturer requires us to sell. Owens Corning’s AttiCat system is our go-to for fiberglass jobs where we need predictable coverage rates and the homeowner wants the non-combustible properties of glass fiber. We’ve installed thousands of bags of their L77 loose-fill in Seguin-area attics and stock their complete range of R-value targets. GreenFiber’s all-borate cellulose is what we reach for in moisture-challenged attics and for homeowners who prefer a recycled-content product with no added formaldehyde. Their SANCTUARY line performs particularly well in the humidity swings we see in Guadalupe County, and we’ve tracked its performance through multiple summer seasons in local homes.
Whether your existing insulation is Owens Corning, GreenFiber, or any other make, we can assess it, match or upgrade it, and document what was done. We don’t require you to stay with the same brand - in fact, we’ll tell you if a different material makes more sense for your situation. The Haven Standard means the recommendation is in writing, with the reasoning, before you decide.
Before
AfterSigns You Need Blown-In Insulation Right Now
- Your upstairs rooms run 8-12 degrees hotter than downstairs in summer. This is the classic symptom of an under-insulated or poorly sealed attic in Seguin’s climate. Hot attic air radiates through the ceiling assembly, overwhelming your HVAC’s capacity to maintain setpoint upstairs. We’ve measured attic floor temperatures above 140°F in Seguin homes during July, and no amount of air conditioning compensates for that thermal load.
- Energy bills spike 30% or more during peak summer months. If your July and August electric bills are double what they were in April, your home is working too hard to replace conditioned air that’s escaping through the attic. The blower-door test we perform quantifies exactly how much air you’re losing - we regularly see pre-sealing readings of 3,500-5,000 CFM50 in Seguin homes that should test below 2,500.
- You can see floor joists in your attic. Insulation should cover joists completely in a properly insulated attic. If the tops of your joists are visible, you have significant gaps in coverage, and settled insulation may be performing at half its labeled R-value. In Seguin’s older neighborhoods like Kingsbury and McQueeney, we find original R-19 batts compressed to R-12 or less after decades of foot traffic and settling.
- Drafty rooms and cold spots appear in winter. Air leaks through the attic floor pull conditioned air upward and draw outside air in through gaps around windows, doors, and foundation penetrations. The drafts aren’t coming from your windows - they’re the result of stack effect driven by a leaky, under-insulated attic envelope. We trace these patterns with thermal imaging during our initial assessment.
- Ice dams form on your roof edges after freezes. Even Seguin’s occasional hard freezes are enough to create ice dams when attic heat melts snow from below, and that water refreezes at the cold eave. Proper insulation and air sealing keeps attic temperature within 10 degrees of outdoor temperature, eliminating the melt cycle that causes dams and the interior water damage that follows.
Our Blown-In Insulation Process - Step by Step
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Initial assessment and blower-door test. We start with a walkthrough of your home and attic, noting existing insulation type and depth, ventilation configuration, and any signs of moisture or pest damage. On jobs where air sealing is included, we run a blower-door test - a pressurization reading that shows, in one number, how much air your building envelope is losing. This becomes your baseline.
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Written scope and flat price. Before any work starts, you receive a written scope specifying exactly what will be sealed, what material will be installed, to what R-value, and what the blower-door target is. The price is flat - no hourly rates, no material surcharges, no “while we’re up there” additions. Haven Standard Clause 1: written price, written scope, written warranty before anyone lifts a tool.
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Air sealing of attic floor and penetrations. We seal top plates, electrical and plumbing penetrations, can light housings, chimney chases, and duct boots with appropriate materials - fire-rated foam, caulk, metal flashing, or gasketed covers depending on the penetration type. This step is never skipped. We’ve documented cases in Seguin where proper air sealing alone reduced blower-door readings by 30% before any insulation was added.
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Blown-in insulation installation. The material specified in your scope is installed to the target depth and density, with continuous measurement during blowing. We photograph coverage patterns, measure depth at multiple points with a ruled probe, and verify that no gaps, thin spots, or wind-washing areas remain near soffit vents.
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Post-work verification and documentation. On air-sealing jobs, we run a second blower-door test and provide the before-and-after numbers. You receive a Documented Photo Record showing attic conditions before, during, and after work, plus the written warranty and any maintenance notes specific to your home. The crew reviews this with you before leaving, and the 365-Day Done Right Promise takes effect immediately.
How Much Does Blown-In Insulation Cost in Seguin?
Most Blown-In Insulation pricing in Seguin falls into these ranges:
| Service | Typical Range | What Affects Price |
|---|---|---|
| Attic top-up (R-30 to R-38, existing insulation in place) | $1,200 - $2,400 | Attic square footage, accessibility, whether air sealing is needed |
| Full attic insulation (R-38 to R-60, including air sealing) | $2,400 - $4,200 | Attic size, complexity of penetrations, material choice (cellulose vs. fiberglass) |
| Dense-pack wall insulation (per 1,000 sq ft of wall area) | $2,800 - $4,800 | Wall cavity access method, existing insulation removal, finish repair scope |
| Blown-in top-up with removal of damaged existing material | $1,800 - $3,400 | Volume of material to remove, disposal fees, extent of air sealing required |
These are real ranges for the Seguin market, based on jobs we’ve completed in neighborhoods from Downtown Seguin to the newer developments along FM 78. The biggest price driver is whether your attic floor needs air sealing before insulation goes in - and in our experience, about 85% of Seguin homes do. Skipping it saves money upfront but costs more in energy bills and often requires re-doing the insulation when moisture problems develop.
What pushes prices toward the high end: attics with limited access (scuttle holes instead of pull-down stairs), extensive can light penetrations requiring sealed housings, existing insulation contaminated by rodents or moisture that must be removed first, and homes with complex rooflines creating multiple attic zones. What keeps prices down: clear attic access, simple rectangular footprint, minimal penetrations, and existing insulation in good condition that only needs topping up.
We don’t do “free estimates” that are really sales presentations - we do written prices before any work starts, and we offer a Free Second Opinion on any written estimate you’ve already received. Bring us a competing quote and we’ll review it with you, line by line, and tell you where the scope differs from what we’d specify. Call (830) 549-6646 to schedule.
Blown-In Insulation Near Seguin - Our Service Area
We work throughout Guadalupe County and into the surrounding metro area, with typical drive times of 15-35 minutes to most locations. Our regular service area includes Blown-In Insulation in New Braunfels, Blown-In Insulation in Cibolo, Schertz, Universal City, Selma, Converse, Live Oak, Windcrest, Kirby, Canyon Lake, Terrell Hills, and all of Seguin proper. Response time for initial assessments is typically next-day to 48 hours, and we schedule installation within a week of written price acceptance for most jobs. Crews are dispatched from our Seguin base, so we’re not driving up from San Antonio and billing you for the transit.
Serving Seguin, TX - Our Local Coverage Area
We’re based in the Seguin area and also provide Blown-In Insulation in New Braunfels and nearby communities. 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 Seguin
Blown-in insulation is loose-fill material - cellulose or fiberglass - installed with a blower hose to create a continuous thermal blanket without the gaps and compression points common with batt insulation. Unlike batts, which are cut to fit between joists and often leave voids around obstructions, blown-in material conforms to irregular attic shapes and provides consistent coverage around ducts, wiring, and framing members.
Most attic jobs are completed in one day, with air sealing adding 2-4 hours depending on penetration complexity. Dense-pack wall insulation typically requires two days: one for access and installation, one for finish repair. We’ll specify the timeline in your written scope before work starts.
A typical attic top-up in Seguin runs $1,200-$2,400, while full insulation with air sealing ranges from $2,400-$4,200. Dense-pack walls cost more due to access requirements. Your written price depends on attic size, material choice, and whether existing insulation needs removal. Call (830) 549-6646 for a flat, written price - estimates are free, and we provide a Free Second Opinion on any competing quote.
Yes - we install and upgrade Owens Corning AttiCat fiberglass systems and GreenFiber cellulose products regularly, and we stock both materials for Seguin jobs. We also work with Johns Manville, Knauf, Rockwool, CertainTeed, Icynene, and Demilec products, so you’re not locked into any single manufacturer’s system.
We answer calls 24/7 and can typically assess urgent situations - significant water intrusion, pest contamination, or insulation collapse - within 24 hours. Same-day installation is sometimes available for straightforward top-ups, though most jobs schedule 2-5 days out to allow for written scope preparation and material staging.
All completed work is covered by our 365-Day Done Right Promise - if it’s not done right, we make it right. The specific warranty terms for materials come from the manufacturer (typically 10 years to lifetime for cellulose and fiberglass products), and our labor warranty is documented in writing before work starts under Haven Standard Clause 1.
Clear attic access paths, remove stored items from the work area, and ensure we have driveway access for our blower truck. We’ll send a preparation checklist when you schedule, and our crew does a walkthrough with you before starting to confirm scope and protect finishes. The Documented Photo Record we provide shows exactly how we left your home.
Schedule Your Blown-In Insulation Service in Seguin Today
Call (830) 549-6646 - a live person answers 24/7 - and we’ll schedule your free assessment, provide a written price before any work starts, and get your home’s envelope performing the way it should. The Haven Standard means flat pricing, documented results, and a crew that shows up when promised. No voicemail loops. No callback windows measured in business days. Just a sealed, insulated home and the numbers to prove it.
Written by Wes Okafor, Owner at Envelope Insulation Co., serving Seguin since 2016.