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Cavity Wall Insulation · Bay Area

Cavity wall insulation for interior and exterior walls

High-performance, blown-in insulation installed through small holes that are patched when we're done. No tearing out drywall, no replacing siding.

  • Non-toxic cellulose made from recycled material
  • Fills cracks and gaps for a seamless barrier
  • Warmer, quieter rooms and lower bills
Free inspection · firm quote

Get your free wall insulation inspection

Tell us where heat, cold or noise is getting through your walls.

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Preview copy: on atticrew.com this card runs Attic Crew's live lead form.

No obligationFirm, written quoteLicensed & insured
Since 2014Family owned Screened & ApprovedHomeAdvisor Licensed & InsuredCA Lic. #1023879 Lifetime Guarantee*On many services
Did you know?

About one third of temperature change in a home comes through uninsulated walls

Energy-efficient homes are insulated from roof to foundation, but many older Bay Area homes were built with little or no insulation in the walls.

Attic insulation should come first, since about a quarter of heat loss is through the top of the home. Then it's time to look at the walls.

Insulating an exterior wall from outside, through small drilled holes.
Insulating an exterior wall from outside, through small drilled holes.
Why cellulose

Non-toxic, blown-in, high performance

Today's wall insulation is made from state-of-the-art materials.

Made from recycled material

Cellulose is made mostly from recycled paper, which helps reduce your carbon footprint.

No fiberglass

Cellulose contains no fiberglass, so there are no itchy glass fibers in your walls.

Seamless coverage

Blown cellulose fills cracks and crevices to create a continuous barrier.

Fire, mold & pest resistance

It's treated with borates, which help it resist fire, mold and insects.

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Empty wall cavities vs. insulated ones

Empty wall cavities vs. insulated onesTap to enlarge
Read this guide as text
  1. BeforeEmpty cavities let cold, heat and outside noise straight through.
  2. AfterCavities completely filled with treated, non-toxic cellulose.
  3. ResultBetter thermal performance, less noise transfer, more fire resistance.
Attic Crew at work

Insulated walls block heat and sound

We use specialist equipment to blow treated cellulose into the cavities of both interior and exterior walls. Insulated walls are a barrier to heat transfer and help soundproof your home.

Attic Crew technicians installing blown-in wall insulation on several homes
Wall insulation projects by Attic Crew.
How it works

Drill, fill and patch

A cavity wall has two faces with a gap between them, the cavity. Most walls, interior and exterior, have one. Installation method and expertise are critical to how well the insulation performs.

  • We drill a planned pattern of small holes
  • Treated cellulose is blown in under pressure until the cavity is completely full
  • Holes are plugged and patched
  • The result: thermal efficiency, sound proofing and fire resistance that should last the life of your home
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Plugging and patching the fill holes after the cavities are full.
Plugging and patching the fill holes after the cavities are full.
Visual guide

How cavity wall insulation goes in

How cavity wall insulation goes inTap to enlarge
Read this guide as text
  1. Blown in through small holesNo tearing out drywall or siding.
  2. Treated, non-toxic celluloseFills the cavity between the drywall and the siding.
  3. Clean, contained work areaFloors and furniture are protected.
  4. The payoffBetter thermal performance, less outside noise, more fire resistance.
Our work

Cavity wall insulation projects

Tap any photo or project to see it full size and step through it.

More cavity wall insulation projects

Blowing insulation into an exterior stucco wall through a drilled port.
Blowing insulation into an exterior stucco wall through a drilled port.Bernal Heights, San Francisco
Checking fill coverage with a thermal camera after insulating a stucco wall.
Checking fill coverage with a thermal camera after insulating a stucco wall.Folsom
Thermal imaging to find under-insulated walls.
Thermal imaging to find under-insulated walls.Sacramento
Touching up the patched fill holes on lap siding.
Touching up the patched fill holes on lap siding.Roseville

Some images show actual Attic Crew jobs; others are representative, with details changed for customer privacy.

See the full gallery

5-star reviews

What our customers say

With 5-star ratings and reviews on Google and Yelp, you can breathe easy knowing you're in good hands.

★★★★★
“This company has done a unrivaled job. They stand behind their reputation and are true to their word. They did insulation clean up, installing new insulation, sanitized and rodent proof. It's only been a few days but you can already tell the different in the temperature of our house!”
Roberta G.Google review
★★★★★
“Attic Crew really saved us! The insulation we had in our house was so ancient, we were using the heater all day and night! After Attic Crew changed our insulation and cleaned our attic, everything became so much better! The house stays cool on the warm days and warm on the cold days.”
Erick P.Google review
★★★★★
“I was looking for a company to do my attic insulation and saw they used Eco bat insulation so I decide to give them a call. Am I glad I did, I never realized what a difference insulation would make! They explained everything to me and made very quick work of the process. I couldn't be happier with the entire experience, from the quote to the final job!”
Winford M.Google review
Common questions

Cavity Wall Insulation FAQ

Do you have to remove drywall or siding?

No. We blow insulation in through small holes drilled in a planned pattern, then plug and patch them.

Is cellulose insulation safe?

Yes. It's made mostly from recycled paper and treated with borates, and it contains no fiberglass.

Will wall insulation make my home quieter?

Yes. Filled wall cavities reduce sound coming in from outside and moving between rooms.

Should I insulate the attic or the walls first?

Usually the attic, since more heat is lost through the top of the home. We'll look at both during the free inspection and recommend the best order.

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Let's get you an estimate

We quote firm prices so there are no surprises. Book your free cavity wall insulation inspection today.

or call 800-558-5857
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