Crawl space vapor barrier in Petaluma CA - a drier, covered crawl space under your house
Musty smell or torn old plastic under the house? We cover the ground edge to edge and tell you straight where the water's coming from.
Get your crawl space looked at
If there's old plastic down there already, mention it when you call (707) 238-6044, because patching a cover and starting fresh are two different jobs.
Do I need a vapor barrier in my crawl space?
A crawl space vapor barrier in Petaluma is heavy plastic laid over the dirt under your house, so less ground moisture and soil gas rises into the crawl space and up into your floors.
Most of the calls I get are from older houses where the dirt under the floor is bare, or where someone put plastic down years ago and plumbers, cable guys and critters have since torn it to ribbons. The price turns on how big the crawl space is, how much has to be hauled out before we can lay anything, how thick a barrier you pick and whether old plastic comes out first. The schedule mostly turns on how easy it is to get under there and whether water from the yard needs fixing before the cover goes down. Once I've been down there, the estimate I write gives you your own number, and we check what the city wants and handle the permit if the job needs one.
Why Petaluma homeowners call Evergreen Petaluma Spray Foam Insulation for a vapor barrier
I crawl under there myself
I learned this trade handing my dad tools in Petaluma crawl spaces, and I still come out for every estimate. You hear what's under your floor from the person who answers for it.
Since 2017, done in order
We've been at this since 2017, and every job still runs the way my dad taught me, water and ground first. That order keeps your money from going into a crawl space that's still wet.
Covered while we're under there
We're licensed and fully insured. Crawl spaces are tight, dark work around pipes and wiring, so you shouldn't be the one on the hook if something goes sideways down there.
Your satisfaction, guaranteed. When you're ready, send us a note or call (707) 238-6044, and I'll come down and have a look.
How we put down a crawl space vapor barrier
First we clear the crawl space of stored boxes, scrap lumber and torn old plastic, because the cover has to reach the whole ground and not just the easy middle. Then we lay the barrier out to the edges, lap the seams and run it up the foundation walls and around the piers, since a cover that stops a foot short leaves the dampest dirt open. My dad's rule was look before you lay, so while we're down there I watch where water is getting in. If it's coming from the yard, from ground that slopes toward the house, a missing drain or sprinklers soaking the foundation, I'll tell you plainly that plastic alone won't fix it and the yard has to come first.
The ground cover is one piece of keeping a house dry. If damp is showing up in walls or a basement too, our vapor barrier installation work handles moisture control beyond the dirt. And because a damp crawl space and a drafty attic tend to live in the same older house, plenty of folks pair this with attic air sealing, so the gaps up top aren't pulling air up from below all day.
A new ground cover
This suits bare dirt, or old plastic so torn and brittle that patching it would be throwing good money after bad. We clear it out and start fresh, edge to edge.
Repairing the cover you have
If the old plastic is mostly whole and the dirt under it is dry, patching and re-lapping the torn spots can be all you need. I'll tell you which one your crawl space calls for.
How can you tell your crawl space needs a vapor barrier?
A musty smell indoors
A damp, earthy smell in rooms over the crawl space usually means moisture is rising off bare dirt. Left alone, it keeps soaking into the wood and insulation under your floor.
Old plastic torn or bunched
Plastic that's ripped, pushed into piles or only covers the middle isn't doing much. Every bare patch lets ground moisture up, so the longer it waits, the less that old cover is worth.
Puddles after a rain
Standing water under the house usually means water is running in from the yard. A cover alone won't stop that, and the longer water sits, the more wood it reaches.
Dark or soft wood
Floor framing that looks stained or feels soft when you press it often means damp has been there a long while. Waiting can turn a ground cover job into a rot repair.
What happens when you call about a crawl space in Petaluma?
Call and set a visit
We get back to you and set a time for me to come out. I crawl under, tell you what I see in plain words and write up your estimate.
Our crew clears and covers
Our crew lead and installers clear out the crawl space and lay the barrier out to the edges. If the city wants a permit, we've sorted it before we start.
We look it over together
I check the finished work with you before we call it done. Bring a flashlight if you want a look underneath, or borrow mine.
Crawl space vapor barrier questions
Here's what Petaluma homeowners ask me most about covering a crawl space. If your house has a wrinkle these don't cover, call and ask, and I'll give you a straight answer.
Does a vented crawl space still need a vapor barrier?
Yes. Federal building guidance says a plastic ground cover belongs down there whether the crawl space is vented or sealed. That makes it a good first step either way, and you can decide about sealing later without redoing the cover.
What is the best thickness for a crawl space vapor barrier?
Thicker lasts longer, and federal weatherization guidance sets 6 mil as the minimum. One cost guide puts a 6-mil contractor sheet at 3 to 5 years and a 20-mil reinforced barrier at 25 years or more. The heavy one costs more up front, so if you're staying in the house, I usually lean toward it over paying to redo a thin sheet every few years.
How much does a crawl space vapor barrier cost in Petaluma?
It comes down to your crawl space, so there's no honest number until I've seen it. Tight access, lots of junk to haul out, old plastic to pull up and a heavier barrier all push the price up, and any drainage fix in the yard is its own job. After I've been under there, the estimate puts your own figure on paper.
How do I get my crawl space ready to be sealed?
Fix the water first. Federal guidance says to deal with drainage problems before turning a vented crawl space into a sealed, insulated one, because sealing in a wet space just traps the water. If I see water coming in from the yard, I'll tell you that has to come before the sealing.
Do I need a permit for a crawl space vapor barrier in Petaluma?
It may need one, because the city's lists don't settle it. Petaluma's Building Division says work not on its list may require a permit, and its list of work needing no permit names French drains and landscaping, not vapor barriers, so we ask the city before we start and handle the permit if one's needed. Dry rot repair is on the city's list that does need a permit, which matters because clearing a crawl space sometimes turns up rot, and you can reach the division at (707) 778-4301.
Does a crawl space contractor need a California license?
Yes, in most cases. The Contractors State License Board requires a license when the job needs a building permit, uses employees or costs $1,000 or more in labor and materials. As I said above, we're licensed and insured for this work.
A free on-site crawl space estimate
Note any standing water, stored stuff or old plastic down there, and we'll reply within one business day to set up my visit. The estimate is free, done on site and comes with no obligation.
Crawl space work up close
Work that pairs with this
Vapor barrier installation
If damp is showing up in a basement or inside walls too, this handles moisture control in the parts of the house beyond the dirt.
Learn moreAttic air sealing
Closing the gaps around lights, pipes and the attic hatch keeps your house from drawing air up from below and makes the upstairs feel less drafty.
Learn more