Wall insulation in Gilroy CA - closed walls filled without tearing them open
Outside walls that feel cold to the touch, or rooms that won't hold heat? We fill the walls through small holes so those rooms stay comfortable.
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How do you insulate walls that are already finished?
Wall insulation in Gilroy usually means filling the closed walls of a house through small holes. That way the rooms hold heat in winter and stay cooler in summer, and nobody tears out drywall or siding to get there.
Most calls start with an outside wall that feels cold to the hand, a bedroom that never warms up, or an older house you just bought where nobody knows what's inside the walls. The price mostly turns on how much wall area we fill, whether we drill from inside or out, which material suits your walls, and whether older wiring or lead paint means extra steps first. The schedule turns on that same prep, since nothing gets drilled until those questions are settled. If most of the heat is escaping overhead, attic insulation may do more for you, and I'll tell you so when I come out and write up your plan.
How we handle a wall insulation job, step by step
First I ask when your house was built and what wiring it has, because older homes need a closer look before we drill. Lead safety rules may apply to homes built before 1980, depending on how much of the wall we disturb. The electrical code also doesn't allow insulation on or around knob and tube wiring, the old porcelain-knob wiring some older houses still have, so if you have it, that gets dealt with before anything else. Once the walls are clear, our installers drill small holes, fill each stud space, check that every one is full and patch the holes. We work in that order because insulation laid over a wiring problem or a leak just hides it.
Walls are only part of how a house loses heat. If you feel drafts around outlets, baseboards or the attic hatch, our air sealing services close those gaps. If the floors stay cold over a lower level, basement insulation is often the next thing on the list.
What shapes wall insulation in Gilroy and across California
The state's energy code is the rule that shapes most wall jobs here. Its manual says that when wood-framed walls are altered and the existing siding stays in place, insulation between the studs can meet the wall requirement. That's what a drill-and-fill job does, so we don't have to strip a stucco wall to do the work right.
Around Gilroy we see a lot of older ranch homes with stucco walls, and plenty of owners who bought an older place and found the outside walls empty or barely filled. Hot valley afternoons push heat through bare walls on the sunny side, so those rooms usually go first on our plan. We're based in Gilroy and work in the cities around it, north into Santa Clara County through Morgan Hill and south toward Hollister, Salinas and Watsonville, and if your city isn't listed, call and ask. If your household's income is limited, the state's weatherization programs offer energy upgrades through local providers, and their help line is (866) 675-6623.
- Call (669) 205-6284
- Mon–Fri: 6 AM–11 PM, Sat–Sun: 7 AM–11 PM
- Gilroy, CA 95020
What happens when you call us about wall insulation?
Call or send the form
I pick up or call you back, and we set a time for me to come out. I'll ask a few questions about the house first, like when it was built and which rooms feel worst.
I look over your walls
I check the walls, outlets, attic and anything that needs fixing before insulation goes in. You get a written plan showing which walls we fill, which side we drill from, the material and anything to fix first, and I walk you through it.
Our installers fill the walls
Our installers follow the order on your plan, covering floors and plants, then drilling, filling each cavity and checking it's full before they patch. I check in while they work so you always know what's next.
We walk the finished job
Before we pack up, I go over the finished walls with you room by room. If anything doesn't look right to you, that's the time to point it out.
Why Gilroy homeowners call Thermal Gilroy Spray Foam Insulation for their walls
The owner writes your plan
I'm the one who looks at your walls and writes the estimate, and I check in while our installers do the work. You have one person to ask, from the first visit to the final walk-through.
Every cavity checked before patching
We make sure every stud space is full before a single hole gets patched, because one skipped bay leaves a cold strip on the wall. If one comes up short, we top it off while the hole is still open.
Licensed and insured in California
We're licensed and insured. The state's licensing board puts insulation under its C-2 insulation and acoustical classification, which covers installing any insulation for heat or sound control, so you know which kind of license covers this work.
Running jobs in Gilroy since 2021
I started this business here in 2021, after years of scheduling crews and learning the trade alongside installers. That's why every job runs in order, with wiring and old paint sorted out before any insulation goes in.
On a wall job, the order of the work matters most, so old wiring and old paint get settled before the first hole goes in. Tell us about your house and I'll set up a time to come out.
Request an estimateGet a written plan for insulating your walls
Send the form and I'll reply within one business day to set up a free on-site visit, where I look over your walls, outlets and attic. There's no pressure to book, and you'll have a written plan in hand before anyone drills.
- Licensed and insured.
- Phone
- (669) 205-6284
- Location
- Gilroy, CA 95020
- Hours
- Mon–Fri: 6 AM–11 PM, Sat–Sun: 7 AM–11 PM
Questions about wall insulation in Gilroy
Can my walls be insulated without tearing them open?
Yes. Most closed walls can be filled through small holes drilled near the top of each stud space, from inside or outside, with blown-in insulation, which is loose fill blown through a hose. Drilling from outside breaks through the wall's water barrier, if it has one, so that layer has to be patched or replaced, while drilling from inside leaves it alone. When the walls give us a choice I lean toward inside, and I'll tell you at the estimate which side yours allow.
Is cellulose or fiberglass better for my walls?
If your walls might ever take on water, fiberglass holds up better, because cellulose breaks down when it's soaked and fiberglass isn't permanently damaged. Fiberglass is also the lighter of the two. Either way, any leak gets fixed before we fill.
How much does wall insulation cost in Gilroy?
Across the US, installed blown-in wall insulation usually runs about $4 to $4.50 per square foot. That's a national figure, not our price. Your number depends on how much wall area we fill, which side we drill from, and whether old wiring or lead paint has to be handled first, and your written plan lays all of that out for your house.
How much do I have to pay up front for insulation work in California?
On a home improvement job in California, a contractor can't ask for or accept a down payment of more than $1,000 or 10 percent of the contract price, whichever is less. Every later payment is listed in the contract and tied to work done or materials delivered, so payments follow the work.
Will insulating my walls stop drafts in my house?
It helps, because cellulose packed tight into the walls cuts a good deal of air leakage. It only works inside the stud bays, though. It won't stop leaks at the rim joist, where the floor framing sits on the foundation, or between floors, or where the walls meet the roof, so in a drafty house we check those spots too.
How do I keep dust and mess down when insulation is blown into my walls?
Ask how the crew will handle dust before work starts, because drilling walls inside the house makes some. Guides on this work describe drill shrouds that catch dust at the bit and plastic sheeting hung floor to ceiling indoors, along with covering shrubs outside. I'll go over how we'll protect your rooms and yard when I come out.
Other work that pairs with wall insulation
Air sealing services
Closes the gaps at the attic hatch, around pipes and along floor edges, the places filled walls can't reach.
Basement insulation
Keeps a chilly lower level from pulling the warmth out of the floors above it.
Book a look at your walls
Have your home's build year, its wiring type if you know it and a rough wall area in square feet ready, and we can plan the visit around your house.
Request an estimateCall (669) 205-6284