Crawl space vapor barrier and cleanout across Snohomish County.

Torn, displaced, or missing plastic, standing moisture, a musty smell, or rodent damage are all signs. If you have had rodents in the crawl space, the barrier almost always needs to come out and be replaced along with the cleanup.

A sheet of polyethylene laid across the dirt floor of the crawl space, usually 6-mil, overlapped at the seams and run up the foundation walls. Bare soil under a house gives off moisture constantly, and without a barrier that moisture goes straight up into your framing, insulation and floors. It is the difference between a dry crawl space and one that grows the soft wood carpenter ants nest in.

Clear the space first, which is most of the work: haul out the old barrier, any contaminated insulation, and whatever the rodents left. Then seal the entry points, because covering the ground without closing the gaps just gives them a fresh sheet to tear up. New 6-mil goes down last, overlapped at the seams and run up the walls. Doing those three as one job is the whole point, and it is why we do not quote the barrier on its own. A vapor barrier installation that skips the first two steps does not last.

It comes down to the square footage of the crawl space and how much cleanup, exclusion, and insulation work it needs, so we price it after we have been under the house. A clean barrier swap is very different from a full rodent decontamination and re-insulation. You get a written quote before any work starts.

Not quite. Full encapsulation seals the crawl space into a conditioned space, often with a heavy liner and a dehumidifier. What we do is vapor barrier replacement, cleanout, and rodent exclusion, which solves the moisture, contamination, and rodent problems most PNW homes actually have, without the cost of a full encapsulation system. If you truly need encapsulation, we will tell you.

Yes, when the contamination comes out. The smell lives in the old droppings, urine-soaked insulation, and nesting material, so we bag and haul all of it, then seal the entry points and lay fresh barrier. Replacing the barrier without removing the contaminated material underneath is why some jobs still smell afterward.

Most PNW homes need it every ten to fifteen years, sooner if there has been rodent activity, flooding, or contractor traffic that tears it up. We will tell you honestly whether yours needs full replacement or just repair.

Yes. Replacing the barrier without sealing the entry points just invites the rodents back. We rodent-proof the crawl space, haul out the old material and debris, and install new six-mil barrier edge to edge.

Bagging and hauling out the old barrier, contaminated insulation, droppings and nesting material, and whatever debris the last contractor left behind. That is the part that takes the time. Sealing the rodent entry points and laying new barrier comes after, because fresh plastic over an uncleaned space just buries the problem instead of solving it.

If the crawl space has a dirt floor, yes. Bare soil gives off moisture around the clock, and it goes straight up into your framing, insulation and floors. Most homes here were built with one, so the real question is usually whether it is still doing its job. A crawlspace vapor barrier that is torn, displaced, or ratted through is doing very little.

Six mil is the standard for a crawl space and it is what we install. Thinner sheeting tears under knees and elbows the first time anyone goes under the house for ductwork or plumbing. Heavier liners exist, and they belong with a full encapsulation system, which is a different job at a different price.