Demilec Crawl Space Encapsulation & Vapor Barrier in New Braunfels: What to Know First
We provide independent Demilec crawl space encapsulation and vapor barrier service in New Braunfels, with most jobs completed in one working day. Most crawl space encapsulation projects in the New Braunfels market run between $3,200 and $6,800 depending on square footage, existing moisture damage, and whether the Demilec foam requires partial removal before we can seal the envelope. We are not affiliated with or authorized by Demilec; we are an independent Demilec service provider with no proprietary product lock-in.
This page is for homeowners who have Demilec spray foam, rigid board, or hybrid insulation in their crawl space and are seeing moisture staining, musty odors, or detached vapor barrier material. If you’re in a neighborhood like River Road near the Guadalupe, or in one of the slab homes built during the 2015-2020 boom around Fischer, your crawl space may be experiencing stack-effect moisture migration that Demilec products alone weren’t designed to stop. Call (830) 243-6352 for a free estimate with a written price before any work starts.
How Demilec Products Fail - and How We Fix Them
- Demilec SEALECTION 500 open-cell foam in rim joists: This series absorbs moisture when the crawl space relative humidity stays above 70% for extended periods, which happens regularly in New Braunfels from March through October. The foam darkens, loses R-value, and can pull away from the wood. We remove the degraded foam, treat the substrate with a mold-resistant primer, then reinstall with a closed-cell alternative or a rigid vapor-barrier assembly depending on the joist cavity depth.
- Demilec Heatlok Soya HFO in below-grade applications: The bio-based content in this series makes it attractive for green builds, but we’ve found it can develop surface pitting when installed directly against earth-coupled block walls without a proper drainage plane. The fix is never just more foam. We install a dimpled foundation membrane first, then reapply only after the wall is properly dried and drained.
- Demilec 2-pound closed-cell on crawl space walls with skipped prep: When the original installer didn’t remove old fiberglass or debris before spraying, the Demilec foam doesn’t bond to the substrate. It delaminates in sheets, creating a vapor barrier that traps moisture behind it. We strip it back to clean masonry, install a mechanical fastener system for the new vapor barrier, and document the substrate condition with photos before we close the wall.
- Demilec hybrid systems with missing ground vapor barrier: Some New Braunfels contractors sprayed Demilec on walls but left the dirt floor bare, or used 6-mil polyethylene that degraded in the alkaline soil common in Comal County. We install 12-20 mil reinforced polyethylene with sealed seams and mechanical fastening to the walls, creating a continuous cap that the original Demilec installation should have included.
- Demilec foam around plumbing penetrations: The Demilec product line is cut back repeatedly by plumbers doing repair work, and the gaps rarely get resealed. We find this in older New Braunfels homes near Landa Park especially, where galvanized supply lines have been replaced with PEX. Our fix is to remove the compromised foam, air-seal the penetration with backer rod and sealant rated for ground contact, then restore the thermal and air barrier with compatible material.
Our Demilec Crawl Space Encapsulation & Vapor Barrier Process
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Call and scheduling: A live person answers, or you can text. We schedule a site visit with a named technician. Under Haven Standard: Arrive on schedule, you get a named technician and a text when they are on the way.
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Diagnostic visit with documentation: We inspect the Demilec installation for the failure modes above, measure humidity and temperature at multiple points, and take baseline photos. If the home has a blower-door history with us, we pull the file by address.
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Written scope and price: You get a flat price, written scope, and written warranty before anyone lifts a tool. Haven Standard Clause 1. No exceptions. We also offer a Free Second Opinion on any written estimate from another contractor.
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Prep and air sealing first: We seal all penetrations, rim joist gaps, and bypasses before installing any new insulation or barrier. The envelope gets tightened before it gets wrapped. We run a blower-door test - a pressurization diagnostic that measures how many cubic feet of conditioned air a house leaks per minute - before and after this phase when the house geometry allows.
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Demilec repair or removal and replacement: We use OEM-compatible materials or quality alternatives from Owens Corning, Johns Manville, Knauf, Rockwool, CertainTeed, Icynene, Demilec, or GreenFiber depending on what the job actually needs. No proprietary lock-in.
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Final test, photo record, and walkthrough: You receive a Documented Photo Record on every visit, plus printed blower-door numbers when applicable. The number on the blower-door printout tells you what the insulation did. Everything else is just talk.
Before
AfterWhat Demilec Crawl Space Encapsulation & Vapor Barrier Costs in New Braunfels
Most crawl space encapsulation jobs in New Braunfels run between $3,200 and $6,800. Here’s what moves you within that range:
- Partial Demilec removal and reinstallation (800-1,200 sq ft crawl): $3,200-$4,500. Limited degradation, intact ground barrier, mostly spot repair and air sealing.
- Full encapsulation with Demilec removal, new ground barrier, wall insulation, and dehumidifier prep: $4,800-$6,800. Includes 12-20 mil reinforced polyethylene, sealed seams, and mechanical fastening to walls.
- Structural moisture damage repair (sill plate, band joist replacement): Add $800-$2,400 depending on linear feet affected. We document with photos and provide written scope before starting.
What moves the price: crawl space height (anything under 18 inches adds labor), active water intrusion requiring drainage, and whether the existing Demilec foam is fully adhered or falling off in sheets. Call (830) 243-6352 for an exact quote - estimates are free, and you’ll get a written price before any work starts.
Why New Braunfels Homeowners Call Topside Attic Insulation New Braunfels for Demilec Work
We’ve sealed and insulated over 9,000 homes since 2016, every one with a written price before work started and a documented record when the crew left. Wes Okafor and our crew have worked neighborhoods all over the New Braunfels area, including jobs off the River Road corridor near the Guadalupe, where stack-effect air leakage in older slab homes tends to run higher than homeowners expect.
We also service Reflectix and other brands, so if your crawl space has a mixed insulation history, we don’t need to call in another contractor. The 365-Day Done Right Promise applies to all completed work. If it’s not done right, we make it right. Calls are answered by a live person 24/7.
FAQs
No - Demilec’s product warranty covers defects in the foam itself, not the conditions where it was installed. As an independent Demilec service provider, we document the pre-existing condition with photos so there’s no dispute about what failed and why. If the foam is defective, we’ll note it in our report and you can pursue that separately. Call (830) 243-6352 if you’d like us to review your installation.
We can source Demilec products when they’re the right choice for the repair, but we’re not locked into any single brand. We also use compatible foams from Icynene and other manufacturers whose formulations perform similarly in Central Texas humidity. The written scope specifies exactly what material goes where - no surprises.
Spot repair is cheaper when less than 20% of the surface area is compromised and the substrate is sound. Full removal makes sense when the foam is delaminating across multiple walls, there’s hidden moisture damage behind it, or the original installation skipped critical prep steps. We price both options in the written scope so you can decide.
Most Demilec crawl space encapsulation jobs are scheduled within 3-5 business days, with emergency water-intrusion calls handled same day when possible. We serve New Braunfels and nearby areas including the Fischer, River Road, and Landa Park neighborhoods. Call (830) 243-6352 to check current availability.
You receive a Documented Photo Record showing before, during, and after conditions; a written invoice matching the pre-approved scope; and on jobs where the house geometry allows, printed before-and-after blower-door readings. We keep a copy of every test report filed by address, which has come in useful more than once when a homeowner sold and the buyer’s inspector asked questions.
Written by Wes Okafor, Owner, Topside Attic Insulation New Braunfels at Topside Attic Insulation New Braunfels, serving New Braunfels and nearby areas.