Demilec Attic Insulation Nationwide

Demilec Attic Insulation: The Boerne Owner’s Guide

Demilec attic insulation replacement in Boerne typically runs $2.80-$4.20 per square foot installed for open-cell spray foam, or $3.50-$5.10 for closed-cell, with most residential attic jobs landing between $3,200 and $6,800 depending on thickness and square footage. We stock Demilec-compatible formulations on our trucks and can usually start the same day you call. Most Boerne homeowners discover their Demilec insulation has failed when they notice hot second-floor rooms in July despite the AC running nonstop, or when a home energy audit reveals the original foam has shrunk away from rafters, creating thermal bypass channels.

Call (830) 529-7780

Which Demilec Models This Applies To

Demilec, now operating under the Huntsman Building Solutions umbrella, produced several formulations relevant to Boerne attics. The SEALECTION 500 open-cell series was common in Texas residential work from roughly 2012-2019, identifiable by a light yellow-cream color and density around 0.5 pounds per cubic foot. The HEATLOK SOY closed-cell series, denser at roughly 2.0 pcf and gray-tan in color, was often specified for cathedral ceilings or conditioned attics where higher R-value per inch was needed.

To identify what you have, check for a Demilec lot label on exposed foam surfaces or on your original invoice. The label includes a formulation code and spray date. If the foam is crumbling, powdering, or pulling away from framing, the lot code helps us match replacement material precisely. We also carry Huntsman-branded equivalents that meet the same ASTM E84 and ICC-ESR certifications as original Demilec stock. For Boerne homes built during the 2015-2018 rush near Balcones Creek, we’ve found SEALECTION 500 that was sprayed too thin in summer heat, leading to shrinkage cracks that don’t appear for several years. OEM Demilec stock is no longer manufactured under that name, so replacement means sourcing Huntsman successor formulations or, in some cases, switching to an equivalent Icynene or CertainTeed open-cell product that matches the existing density and adhesion profile.

Signs Your Demilec Attic Insulation Is Failing

• Hot spots on the ceiling below the attic. When Demilec open-cell shrinks or separates from rafters, convection currents form in the gap. The ceiling drywall becomes a radiator instead of a barrier. We see this most often in Boerne homes where summer attic temperatures exceed 140°F and accelerate adhesive fatigue.
• Musty or chemical odor returning after years of neutrality. Properly cured Demilec is inert, but incomplete initial cure or later moisture intrusion can reactivate residual amines. If your attic smells sharp or acrid, the foam matrix may be breaking down.
• Visible powder or dust on the foam surface. UV degradation attacks exposed Demilec foam, even in attics with limited light leakage. The surface oxidizes and powders, reducing effective R-value. This is common near gable vents or where recessed light housings leak attic air into conditioned space.
• Ice damming or heavy frost on roof nails in winter. Warm, moist air hitting cold roof decking means your insulation has lost contact somewhere. In Boerne’s occasional hard freezes, this shows up as interior nail pops or water stains weeks later.
• Energy bills climbing year-over-year with no rate change. When we blower-door test homes with failing Demilec, we regularly see air leakage double from original construction numbers. The foam hasn’t disappeared; it’s just no longer forming a continuous air barrier.

Replacement Cost & What’s Included

Most Demilec attic insulation replacements in Boerne fall between $3,200 and $6,800 for a complete removal and re-spray of a 1,800-2,800 square foot attic footprint. Smaller partial repairs, typically cutting out failed sections and re-foaming, run $850-$1,900.

What drives the range: attic accessibility (scuttle vs. pull-down stairs vs. no access), existing foam condition (removable in sheets or pulverized), and whether the original was sprayed directly to roof deck or floor joists. We provide a Written Price Before Any Work Starts, always, under Haven Standard Clause 1. The 365-Day Done Right Promise covers adhesion, coverage uniformity, and the air-sealing result verified by blower-door test. You receive a printed pressure-differential report in pascals, plus a Documented Photo Record of before, during, and after.

DIY or Call Us?

Here’s what you can safely check yourself: look at your attic foam in daylight for color change, shrinkage gaps, or powdering. Note any odors. Check your electric bills for unexplained increases. These observations help us diagnose before we arrive.

Here’s where DIY ends: removing old spray foam requires specialized grinding equipment and respiratory protection against isocyanate dust. Re-spray demands precise substrate temperature, humidity control, and mil-thickness monitoring that a handheld gauge provides. Get the mix ratio wrong and the foam never cures properly, leaving you with a sticky, toxic mess. We’ve been called to fix homeowner spray-foam jobs in Fair Oaks Ranch and near Boerne City Lake, and the remediation always costs more than doing it right the first time. Seal the envelope first. Then fill it. Call (830) 529-7780 and we’ll bring the blower door, the grinder, and the right formulation for your specific Demilec replacement.

FAQs