CertainTeed Crawl Space Encapsulation: The Schertz Owner’s Guide
Most CertainTeed crawl space encapsulation systems we replace in Schertz run between $2,800 and $5,400 installed, depending on crawl square footage, existing moisture damage, and whether the original vapor barrier was a 6-mil or 10-mil product. We stock CertainTeed-compatible 10-mil reinforced polyethylene, seam tape, and mechanical fasteners on every truck, and we can usually inspect and start the same day you call. Homeowners typically figure out something’s wrong when the musty smell returns after a rain, or when they notice the HVAC is running longer to pull air through a damp crawl space.
Which CertainTeed Models This Applies To
CertainTeed doesn’t sell crawl space encapsulation as a named system the way they sell roofing or siding; what we see in Schertz homes is CertainTeed 6-mil and 10-mil polyethylene vapor barriers, often installed by builders between 2008 and 2018 as part of a “sealed crawl” spec. The product you’re looking for is usually labeled “CertainTeed Moisture Barrier” or “CertainTeed Poly Sheeting” with a mil rating stamped on the roll edge. If the original installer left a scrap, check for the blue CertainTeed logo and the ASTM E1745 Class A or C rating - Class A is the 10-mil reinforced product, Class C is the thinner 6-mil.
Here’s where owners get tripped up: CertainTeed’s 10-mil reinforced barrier has a woven polyethylene core that aftermarket 10-mil products sometimes skip. The aftermarket stuff measures 10-mil at the thickest point but tears at the seams under crawl traffic. We carry both OEM CertainTeed and a reinforced aftermarket equivalent from a supplier we trust, and we’ll show you the difference side by side before you decide. The OEM runs about 15% higher on material cost. For most Schertz crawl spaces under 1,200 square feet, the total job difference is $300-$450.
We are an independent service provider - not affiliated with CertainTeed - so we have no incentive to push OEM over equivalent aftermarket when the spec matches.
Signs Your CertainTeed Crawl Space Encapsulation Is Failing

- Musty odor returning after rain. The vapor barrier has separated at the seams or pulled away from the foundation walls, letting ground moisture evaporate directly into the crawl space air. In Schertz, our clay-heavy soils hold water for days after a storm, so even a small gap dumps humidity upward.
- Soft or bouncy floors above the crawl. Moisture has reached the subfloor and started delaminating the OSB or plywood. This isn’t a structural failure yet, but it’s the next domino - the encapsulation failed first, the wood is failing second.
- Condensation on ductwork or plumbing lines. The relative humidity in the crawl is staying above 70% because the barrier isn’t blocking vapor transmission. Cold supply ducts sweat first; you’ll see rust on galvanized straps or drip marks on the vapor barrier below.
- White or gray mold on floor joists. Surface mold needs 60% relative humidity to grow. If you’re seeing it, your CertainTeed barrier has been compromised for at least one full season - probably at the perimeter, where Schertz’s seasonal soil movement pulls staples loose.
- Pest activity increasing. Termites and carpenter ants follow moisture gradients. A failed encapsulation turns your crawl space from dry shelter back into a habitat. We see this most in the older Schertz subdivisions north of I-35 where the original 6-mil barriers are past their useful life.
Replacement Cost & What’s Included
For a typical Schertz crawl space - 800 to 1,400 square feet - here’s how the pricing breaks down:
| Component | Price Range |
|---|---|
| 10-mil reinforced vapor barrier (material only) | $1.20-$1.85 per sq ft |
| Foundation wall sealing (butyl tape + mechanical fasteners) | $380-$620 |
| Pier and column wrapping | $45-$75 each |
| Dehumidifier installation (if needed) | $890-$1,400 |
| Labor and removal of failed barrier | $1,100-$1,800 |
| Typical total installed | $2,800-$5,400 |
The wide range comes down to three things: crawl space height (less than 18 inches means more labor), how much of the old barrier has to be cut out and hauled, and whether the foundation walls need prep work - flaking paint, old adhesive, or rodent damage that has to be addressed before new tape will bond. We don’t guess at this. We send a technician with a tape measure and a moisture meter, then deliver a written price before any work starts. Haven Standard Clause 1: flat price, written scope, written warranty before anyone lifts a tool.
Every encapsulation replacement includes a Documented Photo Record - before, during, and after - plus a 365-Day Done Right Promise. If the seams open or the tape fails, we make it right.
DIY or Call Us?

Here’s what you can safely check yourself: look at the perimeter where the vapor barrier meets the foundation wall. If you see gaps, pulled staples, or tape that’s turned to yellowed goo, the seal is compromised. You can also check the center seams - they should overlap 6 inches minimum and be taped with pressure-sensitive seam tape, not duct tape. Duct tape fails in crawl spaces; we’ve all learned that.
Where DIY goes wrong: cutting and seaming 10-mil reinforced polyethylene in a confined space is miserable work, and one wrinkle in the barrier creates a vapor path that defeats the whole job. More importantly, if your crawl space has active mold, disturbed spores become an inhalation hazard without proper PPE and negative air setup. And if the subfloor is already soft, you’re walking on compromised structure in dim light. We’ve replaced too many homeowner attempts where the material was right but the execution turned a $3,500 professional job into a $6,200 remediation.
Call (830) 402-5240 and we’ll inspect it properly. Estimates are free, and we stock the material.
FAQs
A properly installed 10-mil reinforced barrier should last 15-20 years, but in Schertz we’ve seen 6-mil products fail in 7-10 years due to the combination of clay soil expansion against foundation walls and the thermal cycling between our 95°F summers and occasional hard freezes. The 10-mil reinforced product with proper seam taping is what we install now, and we expect it to outlast the original. Call (830) 402-5240 if you’re unsure which product you have - we can tell from a photo.
Patching works for isolated punctures - a torn section under a plumbing repair, for instance - but seam failures and perimeter pull-away are systemic. Tape doesn’t stick well to aged polyethylene, and patching over a failed seal is like caulking over rotted trim. We evaluate each crawl space individually, but if the barrier is more than 8 years old and showing multiple failure points, replacement is the honest recommendation. We offer free second opinions on any written estimate you’ve already received.
Most Schertz crawl spaces take one to two days: half a day to remove the failed barrier and prep the walls, half a day to install and seam the new 10-mil product, plus additional time if we’re adding a dehumidifier or addressing subfloor moisture damage. We don’t rush the seam work - every 6-inch overlap gets rolled with a weighted roller so the tape achieves full adhesion. You’ll get a text when the crew is on the way and a photo log when they leave.
We stock 10-mil reinforced polyethylene, butyl foundation tape, mechanical fasteners, and seam tape on every truck - CertainTeed-compatible specs, plus a reinforced aftermarket equivalent we trust. We don’t stock the thinner 6-mil product anymore; it doesn’t hold up in our local soil conditions. If your job requires a specific CertainTeed SKU for warranty or HOA compliance, we can source it with a two-day lead time. Most homeowners don’t need OEM to get the performance they’re after.
Topside Attic Insulation Schertz also stocks Reflectix radiant barrier products for crawl space and attic applications - we can spec a hybrid system if your home needs both moisture control and heat gain reduction.
Seal the leaks first. Then insulate. The attic doesn’t care how thick the insulation is if the air is still moving through it. That sequencing principle - blower-door test, air sealing, then insulation - is how Wes Okafor built this crew’s reputation, and it’s how we approach every crawl space that connects to the rest of the envelope.
Ready to get it fixed right? Call (830) 402-5240. A live person answers 24/7, and we’ll have a technician out to measure your crawl space and deliver a written price before any work starts.
Written by Wes Okafor, Owner, Topside Attic Insulation Schertz at Topside Attic Insulation Schertz, serving Schertz and nearby areas.