Crawl Space Insulation in Everett, WA
In a vented crawl space, the insulation belongs in the floor above you, packed between the joists and held tight against the subfloor. In a lot of Everett homes it is hanging in loops, lying on the dirt, or was never installed at all. The result is cold floors from November to March and heat you pay for leaking into the crawl space.
This page is about under-floor insulation: when to replace it, what to install, and what the job costs. Send a request and a local contractor will follow up to look at your crawl space.
Call (425) 552-1521
Signs the crawl space insulation needs replacing
- Floors that feel cold under bare feet, especially over bedrooms and bathrooms
- Batts sagging away from the subfloor or lying on the ground
- Insulation that is damp, compressed, or stained dark
- Tunnels, nests, or droppings in the fiberglass
- Bare joist bays with no insulation at all
- Pipes that froze during a cold snap
Request an estimate
- Tell us what’s wrong. A name, a phone number and what you’ve noticed is enough.
- A local crawl space contractor calls you back to book a look underneath.
- You get a price, and decide whether, and when, to go ahead.
For homes in Everett, Marysville, Arlington, Lake Stevens, Snohomish, Stanwood, Mukilteo and Mill Creek.
What an insulation inspection checks
Before quoting new insulation, the contractor should find out why the old insulation failed. Otherwise the new batts can end up in the same condition.
- How much of the floor is covered, and whether batts touch the subfloor or leave an air gap.
- Which way the paper or foil facing points. It should face up, toward the heated floor.
- What holds the batts up: wire supports, twine, netting, or nothing.
- Moisture content of the insulation and the joists above it.
- Rodent activity, which decides whether the old material can stay or has to go.
- Heating ducts and water pipes, and whether they are insulated and connected.
- Air leaks around plumbing, wiring, and duct penetrations into the house.
What affects the cost of crawl space insulation
Most of the price comes from square footage and from what has to happen to the old insulation first.
Square footage of the floor
Material and labor scale with the area of the house over the crawl space. A 1,200-square-foot rambler and a 2,400-square-foot two-story on the same footprint cost about the same to insulate underneath.
Removal and disposal of old insulation
Pulling wet or contaminated batts, bagging them, and hauling them away can take as long as installing new material. Rodent-contaminated insulation takes extra protective gear and care.
Joist depth and clearance
Older homes with 2x8 joists can't hold a full-depth R-30 batt, so the contractor may recommend a different product. Low clearance slows the work.
Material choice
Fiberglass batts are the most common and least expensive choice. Rigid foam or spray foam at the rim joist costs more per square foot but seals air leaks that batts don't.
Ducts and pipes
Resealing and wrapping ductwork, or insulating water lines, is often added while the crew is already under the house.
Insulating crawl spaces in Everett's climate
Everett winters are mild on paper, but the crawl space air sits in the 40s for months and the ground under it never dries out. Floor insulation that stays dry and tight to the subfloor keeps that cold, damp air out of the rooms above. Insulation that sags or gets wet does little.
Washington's energy code calls for R-30 floor insulation over an unconditioned crawl space in new construction. Many Everett homes built before the 1980s have far less, and some of the older houses in north Everett have none. Bringing an older home up to R-30 is often the single biggest comfort change you can make to the floors.
Snohomish County PUD supplies electricity in Everett and has offered weatherization rebates for insulation in electrically heated homes. Programs change, so check the PUD's current rebate list before you schedule work and ask the contractor whether they can meet its requirements.
From request to estimate
- Request an estimate by phone or form and mention cold floors, fallen batts, or pests if you've seen them.
- A contractor inspects the crawl space and confirms that it is dry enough to insulate.
- Old or damaged insulation is removed, and air leaks into the house are sealed.
- New insulation is installed tight to the subfloor and held in place with supports.
Crawl space insulation questions
What R-value should crawl space insulation be in Everett?
R-30 is the target for floors over a vented crawl space under the current Washington energy code. If your joists are too shallow for R-30 batts, ask about the best value that fits without compressing the insulation, since compressed fiberglass loses much of its R-value.
Why does crawl space insulation fall down?
The usual causes are missing supports, moisture that makes the batts heavy, and rodents nesting in them. Gravity wins over time if nothing is holding the batts up. New batts should be supported every 12 to 24 inches.
Which way should the paper facing go?
The kraft paper or foil facing goes up, against the subfloor, on the warm side. Facing installed toward the dirt can trap moisture in the batt.
Should I use spray foam instead of batts?
Spray foam works well at the rim joist and around penetrations where batts leave gaps. Spraying the entire underside of the floor costs a lot more and makes future plumbing and wiring work harder. Most vented crawl spaces are well served by batts with foam at the rim.
Can new insulation go over the old insulation?
Only if the old insulation is dry, clean, and in contact with the subfloor. Wet, moldy, or rodent-contaminated insulation should come out first.