Seal the wet ground, air-seal the rim joist, and skin the space with closed-cell foam — turning a damp, drafty dirt crawl space into a dry, sealed, warmer part of your house. Serving Montana, North Dakota, South Dakota & Wyoming. Veteran-owned and BPI-certified. Free estimate.
An open, vented crawl space breathes. It pulls humid outside air in through the vents, and moisture rises straight out of the bare dirt floor. That damp air chills the floor above, carries a musty smell up through the whole house, and feeds rot in the joists and rim. Old vinyl-faced batts stuffed between the joists sag, fall down, and soak up that moisture — which makes it worse, not better. Encapsulation flips the space: seal it off from the ground and the outside air, insulate the boundary, and the crawl space becomes part of your conditioned house instead of a wet cellar underneath it.
A heavy vapor barrier over the dirt and up the walls stops moisture from ever rising into the space.
Closed-cell foam on the rim joist seals the single biggest air leak in most homes at about R-6.5 per inch.
No damp air rising and no draft through the rim means warmer floors above and a house that holds heat.
Heavy poly laid over the dirt floor and run up the foundation walls, sealed at the seams and edges so the ground can't breathe moisture into the space.
Closed-cell foam on the rim joist and band, plus sealing the old foundation vents — killing the drafts and moisture path that fight your furnace all winter.
Foam the crawl walls (or the subfloor where that's the right call) so the crawl space stays inside the warm envelope of the house.
Where attic or floor heat gain is part of the story, a radiant barrier can pair with the foam — foam handles conductive heat and air, a radiant barrier handles radiant heat. We'll tell you straight which one your building actually needs instead of selling both.
Water doesn't respect the line between "insulation" and "concrete." The same moisture that dampens a crawl space is the water that undermines a slab, washes out voids, and lifts and cracks concrete at the edge. We handle both sides of it: seal the crawl space so the ground stops feeding moisture into the house, and lift and stabilize the concrete when water has already moved the soil under it. If your crawl space is wet, ask us to look at the slab and grading too — it's usually the same water.
Related spray foam topics: Spray Foam Insulation · Open-cell vs closed-cell · Attic insulation · Ice dam prevention · The building envelope
Owner Clifton Behner holds BPI Professional and Technician certifications from the Building Performance Institute. On a crawl space that means the vapor barrier, air sealing, and insulation are specified as one moisture-and-air system for your building — done right the first time, not spray-and-go.
★ Read & leave Google reviewsBased in Glendive, MT — serving the four-state region. Not listed? Call, we travel for the right job.
Sealing the crawl space off from the wet ground and outside air: a heavy vapor barrier over the dirt and up the walls, the rim joist and vents air-sealed, and the space insulated — usually with closed-cell foam. You end up with a dry, sealed space instead of an open dirt cellar breathing damp air into your house.
A vented crawl space pulls in humid outside air while moisture rises out of the bare dirt. That damp air cools the floor above and carries a musty smell up through the house. Sealing the ground and air-sealing the rim joist stops the moisture and the cold air at the source.
Yes — closed-cell foam is both an air barrier and a vapor barrier at about R-6.5 per inch. On the rim joist and walls it seals the biggest air-and-moisture leaks in the building while adding real R-value, so the crawl space stays dry and the floors above stay warmer.
Encapsulation targets the cause — ground moisture and humid air — which is what drives the damp, musty conditions mold and rot need. Sealing the dirt and air-sealing the space dries it out. We don't remediate existing mold, but we fix the moisture problem that feeds it. If you already have active mold or standing water, we'll tell you what has to be handled first.
Yes — $0-down financing through Hearth. Checking your rate is a 60-second soft pull that won't affect your credit.