A musty smell inside
When the house smells damp and nothing upstairs explains it, the source is often bare dirt under the floor. I go under and check before anyone talks about plastic.
Crawl space vapor barrier in Modesto CA - dirt covered and sealed wall to wall
Damp dirt under the floor or a musty smell in the house? We find where the water's coming from, then cover the ground.
- Licensed and insured.
- Free on-site estimates.
- We respond within 1 business day.
What a crawl space vapor barrier does
A crawl space vapor barrier is heavy plastic we lay over the dirt under your Modesto house and seal to the walls and piers, so water and water vapor from the ground stay out of the crawl space. At TempGuard Modesto Spray Foam Insulation, I look under the house myself before we quote it, because the plastic only does its job once the water is handled.
The price mostly comes down to how much floor there is, how much has to come out from under the house before we start, how many piers and how much wall the plastic has to wrap, and which plastic you pick. Sealing the whole crawl space is a bigger job than the cover alone, and we'll talk through both. The schedule turns on whether there's a water problem to fix first, and your estimate spells out what your house needs.
Modesto is home base. We do the same work in Ceres, Salida, Turlock, Manteca and the other cities around it in Stanislaus County, and over into San Joaquin and Merced counties, so call if you're not sure we come out your way.
I look before we quote
I come out myself, get under the house and write the estimate. If plastic won't help until a water problem is fixed, I'd rather tell you that than sell you a cover.
Work done in the right order
Stored stuff comes out, the water source gets looked at, then the plastic goes down. Covering a problem doesn't fix it, it just puts it out of sight under plastic.
I go over the job with you
Our installers do the work, and I check it with you at the end, seams and pier wraps included. We've been in business since 2013, and that last walk-through hasn't changed.
How we lay plastic under your house
First we clear out whatever's stored under the house, because the plastic has to cover the whole floor and it can't go under a stack of old tile. Then I look at where the water is coming from. Wet dirt along one wall usually points to something outside, and that gets fixed before the plastic means anything.
Then our installers lay plastic over the whole floor and run it up the walls and around the piers, overlapping and sealing the seams so no bare dirt is left at the edges. The edges are where rushed jobs usually leave gaps, and a gap is where the damp gets back in.
The crawl space is the bottom of the house, and air leaking out the top pulls air up from underneath, so attic air sealing often belongs on the same list. If you need plastic somewhere other than the dirt floor, such as behind a wall or under new flooring, that's our vapor barrier installation work.
When homeowners call us about the crawl space
Bare dirt or torn plastic
Older houses often have no cover at all, or a few loose sheets that have slid away from the walls. We pull the old pieces and cover the floor fully this time.
Before insulating the floor
Floor insulation hung over damp dirt can soak up moisture and sag. We put the plastic down first, then the crawl space insulation goes in over a covered floor.
Rentals between tenants
Landlords often call when a house is empty, since nothing is stored underneath and our crew isn't working around anyone's schedule. It's also a good time for me to look over the rest of the house.
Get a free crawl space estimate on site
Send the form and we'll get back to you within one business day to set a time. I come out, go under the house myself and write your estimate, free and with no obligation.
Tell us what's stored down there
Boxes, old lumber and leftover tile all have to come out before plastic goes down. Knowing ahead lets us plan the clearing instead of finding it on the day.
Say if a furnace sits there
A water heater or furnace under the house changes what sealing the crawl space involves, as the questions below explain, so it's worth a line when you write.
Mention any water you've seen
Puddles, wet dirt or a damp smell after the sprinklers run all tell me where to look first once I'm under the house with a flashlight.
Crawl space vapor barrier example photos
Example photos of plastic types, seam layouts and pier wraps we can talk through when we're looking at your crawl space together.
Crawl space vapor barrier questions in Modesto
Here's what Modesto homeowners usually ask us before anyone crawls under the house and puts plastic down.
Do I need a vapor barrier if my crawl space has vents?
Yes. Energy Department guidance says the plastic ground cover belongs in a crawl space whether it's vented or not, because vents move air but don't stop moisture coming up out of the dirt. The cover also helps keep soil gases from working their way into the house. Keeping the vents and adding the cover is the simpler of the two jobs.
Will a vapor barrier alone fix a wet crawl space?
Usually not. In a vented crawl space, most of the moisture comes from water getting in through poor grading, missing drainage around the house or how the yard gets watered. So I look at the slope, the drainage and the sprinklers before any plastic goes down. It's fair to ask for a written list of water, moisture or pest damage found before work starts.
Is thicker reinforced vapor barrier plastic worth it?
It is if someone crawls around down there to service a furnace, ducts or plumbing. Basic 6-mil plastic without reinforcement needs protecting along the paths where workers crawl, and thicker reinforced plastic holds up better to that traffic. If nothing under your house gets serviced, the basic plastic usually does the job, and I'll tell you so.
Should I seal my crawl space and close the vents?
It's an option to talk through when I'm out there. Sealing goes further than the cover, closing off the vents and insulating the walls, which also keeps humid outside air out. If a water heater or furnace that vents without a fan sits down there, plan on a combustion safety test after sealing to check that fumes aren't spilling or flowing back.
Do I need a permit for a crawl space vapor barrier in Modesto?
Ask the city before work starts. In Modesto, the city's Building Safety Division issues permits once plans are approved and fees are paid, and permitted work is inspected before it gets covered. When your job needs one, we pull it with the city or county, whichever has your address, and set up the inspection. The city takes permit questions at 209-577-5232.
Does a crawl space vapor barrier installer need a California license?
In most cases, yes. The California Contractors State License Board requires a license for work that alters a building when the job needs a building permit, uses any other workers, or comes to $1,000 or more in labor and materials. A crew job under a house usually crosses at least one of those lines. We're licensed and insured.
Other work that pairs with a crawl space job
Book a look under your house
Call (209) 222-5441 any day between 7 AM and 11 PM, or send the form tonight, and we'll set a time to come out.