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Crawl spaces & basements
Warmer floors start below your feet.
Cold floors, musty smells and high humidity usually begin in the crawl space or basement. Closed-cell spray foam seals and insulates foundation walls and rim joists in one step.
- Rim joists & band boards
- Crawl space & basement walls
- Moisture-resistant closed-cell foam
Why start below
What happens downstairs doesn’t stay downstairs.
Air from your crawl space or basement rises into the living space. Seal and insulate the foundation, and the whole house feels the difference.
Cold floors
Uninsulated crawl spaces and rim joists pull heat right out of the floors above.
The leakiest spot in the house
Rim joists — where the house sits on the foundation — are full of gaps that let outside air pour in.
Musty, humid air
Sealing the crawl space helps keep damp, musty air out of your living space.
Fewer entry points
Sealing gaps and penetrations closes off easy paths for drafts — and helps keep critters out.
Warmer pipes & ducts
Insulating foundation walls helps protect plumbing and ductwork that run below the floor.
Even comfort
A sealed, insulated foundation evens out temperatures across the whole first floor.
Our approach
What we typically recommend
- Closed-cell foam on rim joists and band boards — one of the highest-impact areas in the whole house
- Closed-cell foam on crawl space or basement walls for a sealed, insulated foundation
- Often paired with a ground vapor barrier for a fully sealed crawl space
- Active water or drainage problems should be fixed first — we’ll point out anything we see
Warning signs
Does this sound familiar?
- Cold floors every winter
- Musty or damp smells in the house
- High indoor humidity or condensation
- Sagging or falling fiberglass under the floor
- Drafts along the baseboards
How it works
Simple from start to finish.
Request your estimate
Fill out the quick form with a few details about your home or building. It takes about a minute.
On-site assessment
We look at the space, talk through your goals and recommend the right foam and thickness — with a clear written quote.
Prep & install
The area is protected and the foam is applied by trained applicators in full protective gear. Many projects wrap up in a day or two.
Feel the difference
Cleanup, a final walk-through, and a quieter, more comfortable, more efficient space from day one.
FAQ
Crawl space spray foam questions
Should I insulate the crawl space walls or the floor above?
In many homes, sealing and insulating the crawl space walls and rim joists — instead of stuffing fiberglass between the floor joists — creates a drier, more comfortable space and protects pipes and ducts below the floor. We’ll recommend the best approach after seeing your crawl space.
Is spray foam OK in a damp crawl space?
Closed-cell foam is water-resistant and well suited to crawl spaces. Active water problems — standing water, drainage issues or leaks — should be fixed first. We’ll flag anything we see during your estimate.
Are basement rim joists really worth insulating?
Yes. Rim joists are one of the best-value places to use spray foam, and ENERGY STAR specifically lists basement rim joists as a key area to air seal and insulate.
What happens to the old fiberglass under my floor?
If it’s sagging, wet or falling down, it’s typically removed. Any removal is included in your quote.
Free crawl space estimate
Get a free crawl space & basement estimate.
Tell us what you’re working on. We’ll follow up to schedule a free on-site assessment and give you a clear, written quote — no pressure, no obligation.
- Free on-site assessment & written quote
- Honest open-cell vs. closed-cell recommendation
- Homes, pole barns, shops & commercial buildings
Get your free estimate
Tell us about your project and we’ll reach out to set up your free, no-pressure assessment.
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