Demilec Crawl Space Encapsulation & Vapor Barrier Nationwide

Demilec Crawl Space Encapsulation & Vapor Barrier in Canyon Lake: What to Know First

We provide independent Demilec crawl space encapsulation and vapor barrier service in Canyon Lake, typically scheduling within 24-48 hours and completing most jobs in a single day. Most Demilec crawl space jobs in Canyon Lake run between $2,800 and $5,400 depending on whether we’re addressing a failing open-cell application in a pier-and-beam foundation or installing a full encapsulation with dehumidification. This page is for homeowners who know they have Demilec product in their crawl space and want a technician who understands how that specific foam behaves in the Hill Country humidity cycle, not a generic encapsulation crew that treats all spray foam the same. Call (737) 227-6219 for a written price before any work starts.

Call (737) 227-6219

How Demilec Products Fail - and How We Fix Them

• Demilec Sealection 500 open-cell in vented crawl spaces pulls bulk moisture. We’ve pulled this product off rim joists in Canyon Lake homes near Startzville where the crawl space vents were left open per old code, and the foam had reached 15% moisture content by weight. Our fix: remove the degraded foam, seal the vents, install a 20-mil reinforced vapor barrier with sealed seams, and condition the space so the replacement insulation doesn’t face the same humidity load.
• Demilec Heatlok HFO High Lift shrinks at the stud bay edge in temperature swings. This closed-cell product performs well when protected, but in unconditioned crawl spaces with our 40-degree winter lows and 100-degree summer highs, we’ve measured 1/8-inch to 3/16-inch shrinkage gaps at the perimeter. We cut back the separated foam, reapply with a compatible HFO formulation rated for the wider delta-T, then verify adhesion with a pull test before closing the cavity.
• Demilec Sealection Agribalance degrades when rodents have accessed the crawl space. The bio-based content attracts nesting; we’ve found this in three Canyon Lake homes off FM 2673 where field mice had burrowed through compromised foundation vents. We remove the contaminated foam, sanitize the substrate, install rodent-proof stainless mesh at all penetrations, then reapply with a non-bio-based closed-cell product in the affected zones.
• Demilec Heatlok XT overspray on ductwork creates condensation drip points. When this higher-density closed-cell is applied directly to flex duct in a humid crawl space, the thermal bridge at the interface can drop surface temperature below dew point. We strip the foam from the duct jacket, install a proper thermal break with reflective insulation, then re-encapsulate the crawl space walls with the ductwork thermally isolated.
• Demilec open-cell installed before 2018 lacks the current vapor retarder facing. Early Sealection 500 applications in Canyon Lake’s 2015-2017 build wave were often left exposed to crawl space air. Without the .1 perm facing now standard, that foam acts as a reservoir for seasonal humidity. We retrofit with a standalone polyethylene vapor barrier or, where access allows, overlay with a flash coat of closed-cell to create the necessary permeance asymmetry.

Our Demilec Crawl Space Encapsulation & Vapor Barrier Process

1. 1
   Conditioned-space assessment first. We run a blower-door test - a pressurization diagnostic that measures how much conditioned air your house is losing through gaps - before entering the crawl space, because a leaky envelope above will sabotage any encapsulation below.
2. 2
   Demilec-specific inspection and documentation. We identify the product line, installation date if traceable, and map failure zones with photos that go into your Documented Photo Record.
3. 3
   Parts decision: OEM Demilec or compatible aftermarket. For repairs where Demilec stock is back-ordered from their Texas distribution, we use HFO formulations from Icynene or Johns Manville that match the original density and R-value, documented in your written scope so warranty coverage remains transparent.
4. 4
   Removal, substrate prep, and reapplication. We cut out failed foam with hot-wire tools, HEPA-vacuum the residue, treat for mold if moisture damage is present, then install the replacement system - whether that’s repaired Demilec product, a full encapsulation with 20-mil barrier, or a hybrid wall-foam plus floor-barrier approach.
5. 5
   Post-work verification. On applicable jobs, we run a second blower-door test and provide the before-and-after readings. Every job closes with your written scope, warranty, and Documented Photo Record.
6. 6
   365-Day Done Right Promise activation. Under Haven Standard: if the crawl space humidity climbs back above 60% RH within a year, we return and make it right.

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What Demilec Crawl Space Encapsulation & Vapor Barrier Costs in Canyon Lake

These are the numbers we put in writing before anyone starts. Not estimates that balloon - a flat price, written scope, written warranty. Bring us a competing quote; we offer a Free Second Opinion on any written estimate. Call (737) 227-6219 to schedule.

Why Canyon Lake Homeowners Call Topside Attic Insulation Canyon Lake for Demilec Work

We’ve been in enough Canyon Lake crawl spaces to know that a Demilec job isn’t a generic encapsulation with a brand name pasted on. Wes Okafor and our crew understand the difference between Sealection 500 and Heatlok HFO shrinkage behavior because we’ve removed and replaced both in this specific Hill Country humidity. Our 365-Day Done Right Promise applies to every completed job, and we answer calls with a live person 24/7 - no voicemail loops when your crawl space dehumidifier alarms at 10 PM on a Saturday. We also service Reflectix and other brands, so if your crawl space has a mixed insulation history, we don’t need to subcontract the diagnosis. Seal the leaks first. Then insulate. The report tells you whether it worked.

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