Vapor barrier installation in Gilroy CA - a sealed ground cover under your house
Musty smell or torn old plastic under the house? We sort out the damp first, then lay a sealed cover that keeps ground moisture down.
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Does my crawl space need a new vapor barrier?
Vapor barrier installation in Gilroy, CA means laying a plastic ground cover over the dirt floor of your crawl space, the short space under a raised floor. It keeps damp from the soil away from the framing and makes it harder for soil gases to get into your house.
Most people call us after they've spotted torn plastic or none at all under the house, or right after buying an older place. The price mostly comes down to how big the crawl space is and what has to happen before the plastic goes down. The schedule turns on any standing water, mold, rotten wood or hazardous materials down there, because those get fixed before a new cover goes in. We're based in Gilroy and work in the cities around it, north into Santa Clara County and south toward Hollister, Salinas and Watsonville, and your estimate gives you a written plan with your own numbers.
How we handle vapor barrier installation
First I find out where the damp is coming from, because plastic laid over a wet crawl space just traps the problem underneath. I check for standing water, mold and rot, and I walk around the outside to see how the ground slopes and where the sprinklers land, since grading and watering are often where the damp starts. Once any fixes are done, our installers lay the plastic over the whole floor, overlap and seal the seams, seal around pipes that come up through the dirt, and run the edges up the walls and piers and fasten them. If you have a sump pit, a small hole that collects water so a pump can push it out, we make sure water still reaches it the way it does now. If your old plastic is mostly whole, I'll show you a repair option next to a new sealed layer so you can choose.
With the ground covered, the next drafts usually come from the top of the house. Attic air sealing closes the gaps around lights, pipes and the attic hatch so the insulation up there isn't fighting a draft. On an older house, retrofit insulation adds what the house was built without.
Vapor barrier installation in Gilroy and the flood question
Parts of Santa Clara County are prone to flooding every year whenever storms come through, and some parcels are still in the FEMA flood zone even after flood protection projects. It's worth knowing where your lot stands before you plan crawl space work. Valley Water answers basic questions on flood zones, insurance and mapping at 408-630-2650 or CPRU@valleywater.org. I'll ask about it at the estimate, because a lot that takes on water changes what has to happen before the plastic goes down.
Under raised-floor houses around here, we often find old plastic that's torn, pulled loose from the walls or buried under boxes. We see the same thing on jobs in Morgan Hill and San Martin, so I plan the clearing into the estimate instead of leaving you to discover it on install day.
- Call (669) 205-6284
- Mon–Fri: 6 AM–11 PM, Sat–Sun: 7 AM–11 PM
- Gilroy, CA 95020
What happens when you call about a vapor barrier in Gilroy?
Call or send the form
You call and I answer, or I get back to you. I'll ask a few questions, like how old the house is and where the crawl space hatch is, so I know what I'm walking into.
I look under your house
I check the old plastic, the dirt, the framing and the ground outside, and I note anything that needs fixing first. You get a written plan that lists those fixes, the cover I'd suggest and what changes the cost.
Our installers work in order
Any water, mold or rot work happens first, then the clearing, then the cover goes down. I check in while they work so you always know what's next.
We walk the finished job
Before we pack up, I go over the finished crawl space with you, seams and edges included. If something doesn't look right to you, that's the time to say so.
Why Gilroy homeowners call Thermal Gilroy Spray Foam Insulation for vapor barriers
The owner writes your estimate
I'm the one who looks under your house and writes the plan, and I check in while our installers do the work. You have one person to ask who already knows your crawl space.
Fixes planned before the plastic
I spent years lining up crews and jobs for a busy company, so I set the order before anyone crawls under, with water, rot or mold work ahead of the cover. Plastic laid over a problem only hides it, and that's the mistake I'm here to save you from paying for twice.
Licensed and insured under your house
We're licensed and insured. That matters when a crew is working around the pipes, wiring and supports that hold up your floor.
Started in Gilroy in 2021
I started this business in Gilroy in 2021 and we've been at it five years. We're still small enough that you call and talk to me.
What matters most under a house is dealing with the damp before the plastic goes down, so call or send us a few details and I'll come take a look.
Request an estimateGet a free written plan for your crawl space vapor barrier
We reply within 1 business day, and I'll set a time to come out for a free on-site look at your crawl space, with no pressure to book. I'll note anything that needs fixing first and walk you through a written plan before you decide anything.
- Licensed and insured.
- Phone
- (669) 205-6284
- Location
- Gilroy, CA 95020
- Hours
- Mon–Fri: 6 AM–11 PM, Sat–Sun: 7 AM–11 PM
Questions about vapor barrier installation in Gilroy
Do I need a vapor barrier if my crawl space is vented?
Yes, crawl space guidance says a plastic ground cover should go in whether your crawl space is vented, with openings in the foundation walls to let air through, or closed up. In a vented crawl space, most of the damp is water seeping in from the way the ground slopes, missing drainage along the foundation or watering too close to the house.
Can an old crawl space vapor barrier be repaired instead of replaced?
Often, yes, if the old plastic is only loose from the walls or open at the seams, because tears and seams can be taped and the edges fastened back to the walls and piers. A new sealed layer over the top lasts longer, and if the old plastic is torn in a lot of places, that's the way I'd lean. Either way, the work is backed by our satisfaction guarantee.
What happens before a vapor barrier is installed in a crawl space?
Stored items and debris get cleared out so the plastic can cover the whole floor. Plants and anything sharp, like nails, wood scraps, glass and sheet metal screws, come out too, so nobody gets hurt and nothing punctures the sheeting. If you'd rather move your own things out ahead of time, just tell me at the estimate.
Who is allowed to install a vapor barrier in California?
Any job over $1,000 calls for a licensed contractor in California. The state lets an unlicensed person take work up to that amount only when the job needs no permit and they have nobody working for them on it, so ask anyone you're considering for their license.
How much does vapor barrier installation cost in Gilroy?
Your price comes from the on-site estimate, because it depends on how big the crawl space is, how easy it is to get in and move around, and how much has to be cleared out first. Repairing old plastic usually costs less up front than a new sealed layer, thicker reinforced sheeting costs more than plain plastic, and any water, mold or rot work adds to the total. I write each of those into the plan so you can see where the money goes.
What is the best vapor barrier material if my furnace or ducts are in the crawl space?
Thicker, reinforced sheeting is the better pick when equipment sits down there, because it holds up better where people kneel and crawl to service it. Guidance says plain plastic should be protected along those paths, so I'll show you where that applies under your house.
Other work that pairs with a crawl space cover
Attic air sealing
Closes the gaps up top that let hot or cold air pull through the house, the other end of the same draft.
Retrofit insulation
Adds insulation to an older house that came with little or none, a good next step once the crawl space is dry and covered.
Book your crawl space vapor barrier estimate
Jot down where the crawl space hatch is, whether you've seen standing water or old plastic, and what's stored down there, and the visit goes quicker.
Request an estimateCall (669) 205-6284