Insulation in Sunnyvale, CA
Spray foam insulation in Sunnyvale runs $2,500 to $9,800 depending on the job, and it’s the fix we recommend most often for Eichler homes and 1950s-1970s ranchers where flat roof decks and empty 2×4 wall cavities defeat conventional attic work. Blown-in insulation typically falls between $1,800 and $4,200, but Sunnyvale’s specific housing stock means some homes need spray foam or rigid board instead of anything blown. Call us at (669) 215-4805 and we’ll tell you which one your house actually needs, not just the one we’d rather sell.
Why Sunnyvale Homes Are Different
Sunnyvale holds one of the Bay Area’s highest concentrations of Eichler homes. These mid-century modern builds have flat or shed roofs, radiant slab heating, and almost no original wall or roof-deck insulation. That changes everything about how insulation gets done here. A homeowner in the Borregas or Lakewood tracts calling for an attic insulation quote often gets caught off guard when we explain there’s no attic cavity at all: the flat roof deck needs spray foam applied to the underside of the decking from inside, or rigid foam added above the deck during a re-roof. Both options require permits and crews who know Eichlers, which most generalist insulation contractors in the region don’t have.
The rest of Sunnyvale’s housing stock dates to the 1950s-1970s semiconductor and aerospace boom: wood-framed ranch homes built fast, with 2×4 walls, little or no cavity insulation, and attics that fall well short of California Title 24’s current R-38 to R-49 requirements. ADU additions and whole-home renovations driven by Sunnyvale’s property values are now a major trigger for insulation upgrades. And the climate matters too: Sunnyvale sits far enough inland that summer Diablo wind events regularly push temperatures into the low-to-mid 90s. The insulation conversation here is about cooling comfort and attic radiant-heat reduction, not the heating-first approach you’d hear from contractors on the coast.
Our Main Sunnyvale Services
Two jobs dominate our Sunnyvale workload more than any others: attic insulation in the ranch homes that fill most neighborhoods, and crawl space encapsulation in the slab-edge and vented-crawl construction we see throughout the city’s older tracts. Here’s what each involves locally.
Attic Insulation in Sunnyvale
Most Sunnyvale ranch homes have attics that never met current code even when they were new, and decades of settling and heat exposure haven’t helped. We blow in Owens Corning or Johns Manville fiberglass to bring ceiling assemblies up to R-38 or R-49, and we air-seal the attic floor at the same time because that’s where Sunnyvale homes lose the most conditioned air in summer. For Eichler homes, the job is different: no attic cavity means we insulate the roof deck instead, which is a spray foam or rigid board conversation, not a blown-in one. Attic Insulation in Sunnyvale covers both paths in detail.
Crawl Space Encapsulation & Vapor Barrier in Sunnyvale
Vented crawl spaces are common in Sunnyvale’s older homes, and they pull in damp air all summer, which then gets drawn up into the living space by the stack effect. We seal the crawl, lay a reinforced vapor barrier, and condition the space so your floors stop feeling clammy and your indoor humidity drops. For homes with radiant slab heating, the crawl space is often the only accessible area beneath the living space, which makes it the best place to add meaningful insulation without tearing walls apart. Crawl Space Encapsulation & Vapor Barrier in Sunnyvale explains how the job is done and what it costs.
What happens when you call
- 1
A real person answersNo phone trees - you reach a local pro.
- 2
You get an upfront price rangeHonest numbers before anyone is dispatched.
- 3
A background-checked tech heads outLicensed & insured, dispatched right away.
- 4
You approve before work beginsNothing starts until you say go.
Spray Foam Insulation in Sunnyvale
Spray foam insulation in Sunnyvale is the highest-leverage upgrade for Eichler homes and any flat-roof or low-slope build where there is no attic cavity to fill. Closed-cell foam applied to the underside of the roof deck does the job that blown-in attic insulation physically cannot, and it also air-seals the entire assembly in one pass. For the 1950s-1970s ranch majority, we use open-cell on rim joists, garage ceilings, and wall cavities to stop the air leaks that make Diablo-heat weeks so punishing. We install Spray Foam Insulation using Icynene, Demilec, and Johns Manville products, and every job carries the Done Right Promise: if it’s not done right, we make it right, no runaround.
Open-Cell Spray Foam
Signs you need it
Rooms over unconditioned garages stay hot in summer while the rest of the house cools, and your energy bill shows the strain.
What it costs in Sunnyvale
Open-cell spray foam in Sunnyvale typically runs $1.50 to $3.00 per board foot installed.
How we do it
We mask off the work area, spray the foam into the cavity or onto the roof deck, let it expand and cure, then trim it flush and verify depth before we leave.
Closed-Cell Spray Foam
Signs you need it
Your Eichler or flat-roof home has no attic, so heat radiates straight through the roof deck into the living space all afternoon.
What it costs in Sunnyvale
Closed-cell spray foam in Sunnyvale typically runs $2.50 to $5.00 per board foot installed, and under-deck applications on Eichlers land at the higher end.
How we do it
We spray the foam directly onto the underside of the roof deck from inside, building up to code depth, then leave the foam exposed or cover it per fire code.
What Spray Foam Insulation Costs in Sunnyvale
| Item | Typical range in Sunnyvale |
|---|---|
| Open-cell spray foam (per board foot) | $1.50 – $3.00 |
| Closed-cell spray foam (per board foot) | $2.50 – $5.00 |
| Full under-deck Eichler roof deck (installed) | $5,000 – $9,800 |
Does spray foam work on Eichler roof decks?
Yes. Closed-cell spray foam applied to the underside of the roof deck is the standard fix for Eichler homes in Sunnyvale because there’s no attic to insulate. It air-seals and insulates in one pass. Call (669) 215-4805 for a site-specific quote.
Can you do spray foam the same day in Sunnyvale?
Smaller jobs like rim joists or garage ceilings can often be scheduled same-week. Full Eichler roof-deck jobs need a day or more. We answer the phone live, so call (669) 215-4805 and we’ll tell you straight.
Blown-In Insulation in Sunnyvale
Blown-in insulation in Sunnyvale is the most cost-effective way to bring a ranch home’s attic up to Title 24’s R-38 or R-49 standard when there’s a conventional attic cavity to work with. Most homes built during the semiconductor boom left the factory with a few inches of settled fiberglass or nothing at all. We blow Owens Corning or Knauf fiberglass or GreenFiber cellulose over the existing attic floor after air-sealing, and we also Blown-In Insulation dense-pack into existing walls when the sheathing allows it.
Blown-In Cellulose
Signs you need it
Your attic insulation measures under R-19, or you can see bare drywall between joists when you look up from the attic hatch.
What it costs in Sunnyvale
Blown-in cellulose in an average Sunnyvale attic typically runs $1,000 to $3,000 installed.
How we do it
We seal the attic floor penetrations, blow cellulose to the target depth, then rake it level and verify R-value with a depth gauge.
Blown-In Top-Up
Signs you need it
Your home stays warm upstairs well into the evening in summer even after the sun goes down and the outside air cools.
What it costs in Sunnyvale
A top-up over existing attic insulation in Sunnyvale typically runs $800 to $2,200 depending on depth needed.
How we do it
We measure the existing insulation, calculate the gap to R-38 or R-49, blow in the difference, and document the final depth.
What Blown-In Insulation Costs in Sunnyvale
| Item | Typical range in Sunnyvale |
|---|---|
| Full attic blow-in (standard ranch home) | $1,000 – $3,000 |
| Blown-in top-up over existing insulation | $800 – $2,200 |
| Dense-pack walls (per wall section) | $1,500 – $4,000 |
Is blown-in insulation enough for Sunnyvale summers?
For homes with a conventional attic, yes, when installed to R-38 or R-49 with proper air sealing. It won’t fix radiant-heat problems on flat-roof Eichlers, which need a roof-deck approach. Call (669) 215-4805 to figure out which one you have.
How long does blown-in installation take?
Most Sunnyvale attics are done in half a day to a full day. Dense-packing walls adds time. We’ll give you a straight answer when you call (669) 215-4805.
Radiant Barrier Installation in Sunnyvale
Radiant barrier installation in Sunnyvale targets the specific problem of attic heat radiating down into the living space during the city’s 90-degree Diablo wind days. A radiant barrier stapled to the underside of the rafters reflects a big share of that radiant heat before it ever reaches the insulation. For ranch homes with conventional attics, we pair the barrier with Radiant Barrier Installation using heavy-gauge foil, and for some homes we add ventilation upgrades at the same time because Sunnyvale attics often lack adequate airflow.
Attic Radiant Barrier
Signs you need it
Your ceiling is warm to the touch on hot afternoons even though the attic insulation measures okay.
What it costs in Sunnyvale
Attic radiant barrier in a typical Sunnyvale ranch attic runs $1,200 to $3,500 installed.
How we do it
We staple perforated foil to the underside of the rafters, leaving the ridge and soffit vents clear, and overlap seams by a few inches.
Radiant Barrier & Ventilation
Signs you need it
Your attic hits 140°F or more in summer and your vents are undersized or partially blocked.
What it costs in Sunnyvale
Combined radiant barrier and ventilation upgrades in Sunnyvale typically run $2,500 to $6,000.
How we do it
We assess airflow first, install or upgrade soffit and ridge vents, then hang the barrier so it works with the new airflow, not against it.
What Radiant Barrier Installation Costs in Sunnyvale
| Item | Typical range in Sunnyvale |
|---|---|
| Attic radiant barrier (standard attic) | $1,200 – $3,500 |
| Radiant barrier plus ventilation upgrades | $2,500 – $6,000 |
| Roof deck radiant barrier (new construction or re-roof) | $1,800 – $4,500 |
Does a radiant barrier help in the winter in Sunnyvale?
Marginal in the winter, but winter heating is not the main problem here. The payoff is summer cooling load reduction, which is what Sunnyvale homeowners feel most. Call (669) 215-4805 for a straight read on your attic.
Can you install a radiant barrier in an Eichler?
No conventional attic means no place to staple a barrier, so Eichler homes need a roof-deck approach instead, usually spray foam or rigid board. We’ll explain exactly what your roof type needs if you call (669) 215-4805.
Insulation Removal & Replacement in Sunnyvale
Insulation removal and replacement in Sunnyvale is the right move when old attic insulation is compacted, water-damaged, or full of rodent droppings, and it’s especially common in the 1950s-1970s ranch homes where original insulation has had six or seven decades to break down. We remove the old material, sanitize the space, then install new insulation to current Title 24 levels. We handle Insulation Removal & Replacement jobs that other insulation contractors in Sunnyvale won’t touch, including vermiculite, and background-checked, uniformed technicians do the work.
Attic Insulation Removal
Signs you need it
Your attic insulation is dark, matted, and half its original depth, or you can see water stains and rodent trails across it.
What it costs in Sunnyvale
Attic insulation removal in a typical Sunnyvale home runs $1,500 to $4,500 before new material.
How we do it
We run a commercial HEPA-filtered vacuum from the attic to a sealed collection bag outside, then haul the waste away.
Vermiculite & Old Insulation Removal
Signs you need it
You see shiny, pebbly material in your attic that could contain asbestos, or you have original 1950s-60s insulation you don’t want to leave in place.
What it costs in Sunnyvale
Vermiculite removal in Sunnyvale costs more than standard removal, typically $3,000 to $7,000 depending on volume and testing requirements.
How we do it
We test first, then remove under containment protocols, and document the disposal paperwork so you have a clean record.
What Insulation Removal & Replacement Costs in Sunnyvale
| Item | Typical range in Sunnyvale |
|---|---|
| Attic insulation removal (standard home) | $1,500 – $4,500 |
| Vermiculite or suspect material removal | $3,000 – $7,000 |
| Removal plus full replacement (cellulose or fiberglass) | $2,500 – $6,500 |
Do I have to remove old insulation before blowing in new?
Usually not. We can blow over clean, dry fiberglass that’s still in decent condition. But water-damaged, rodent-contaminated, or vermiculite insulation should come out first. Call (669) 215-4805 and we’ll tell you what yours needs.
How long does removal take?
Most Sunnyvale attic removals take one full day. Vermiculite jobs take longer because of the containment and testing steps. The phone is answered by a live person 24/7 at (669) 215-4805 if you want to schedule.
Attic Air Sealing in Sunnyvale
Attic air sealing in Sunnyvale stops the stack effect that pulls hot attic air down into your living space every summer afternoon while also losing conditioned air through the ceiling. The 1950s-1970s ranch homes here were built with more gaps than current practice allows: recessed can lights, plumbing chases, top plates, and poorly sealed attic hatches all leak. We seal those paths as part of every attic job and as a standalone Attic Air Sealing service using foam, caulk, and weatherstripping.
Attic Floor Air Sealing
Signs you need it
You can feel drafts near ceiling fixtures in winter and your upstairs rooms take hours to cool down in summer.
What it costs in Sunnyvale
Attic floor air sealing in a typical ranch home runs $800 to $2,500 depending on attic size and access.
How we do it
We move insulation aside, seal every ceiling penetration from above with foam or caulk, then re-lay the insulation.
Can Light & Duct Boot Sealing
Signs you need it
Recessed lights and duct registers feel warm on hot days, and dust lines radiate outward from ceiling penetrations.
What it costs in Sunnyvale
Sealing can lights and duct boots in a typical Sunnyvale home runs $400 to $1,500.
How we do it
We install rated covers over non-IC lights, foam-seal duct boots at the drywall, and verify each seal with a smoke pencil.
What Attic Air Sealing Costs in Sunnyvale
| Item | Typical range in Sunnyvale |
|---|---|
| Full attic floor air sealing | $800 – $2,500 |
| Can light and duct boot sealing | $400 – $1,500 |
| Attic hatch sealing and weatherstripping | $150 – $400 |
Can air sealing alone fix my comfort problem?
Air sealing makes a bigger comfort difference than most people expect, especially in Sunnyvale ranch homes with leaky ceiling planes. But it pairs with insulation, not replaces it. Call (669) 215-4805 for a straight answer about your house.
How do I know if my attic is leaking air?
The surest way is a blower door test, which measures total air leakage. Visual signs include dirty insulation around penetrations and warm ceiling spots. We can test for you; call (669) 215-4805.
Wall Insulation in Sunnyvale
Wall insulation in Sunnyvale matters because so many of the city’s wood-framed ranch homes and Eichler tracts left the factory with 2×4 walls that had zero cavity insulation. Exterior walls that bake in the Diablo sun all afternoon transfer that heat straight inside, and that problem doesn’t go away by insulating the attic. We use Wall Insulation methods including drill-and-fill dense packing and injection foam, and for Eichler homes with no wall cavity at all we add rigid foam on the exterior or interior where re-roof and renovation timing allows.
Drill & Fill Wall Insulation
Signs you need it
Rooms with exterior walls feel hot in summer even when the AC runs, and walls feel warm to the touch on sunny afternoons.
What it costs in Sunnyvale
Wall insulation in a typical Sunnyvale home runs $2,500 to $7,000 depending on wall area and method.
How we do it
We drill small access holes through the siding or drywall, dense-pack the cavity through each hole, then patch and texture the holes.
Injection Foam Wall Insulation
Signs you need it
Your walls have enclosed cavities but no insulation, and you can hear exterior noise clearly through the wall assembly.
What it costs in Sunnyvale
Injection foam in existing walls typically runs $4,000 to $9,000 for a whole house in Sunnyvale.
How we do it
We inject slow-expanding foam into each stud bay from small holes, checking fill with a thermal camera as we go.
What Wall Insulation Costs in Sunnyvale
| Item | Typical range in Sunnyvale |
|---|---|
| Drill-and-fill dense pack (whole house) | $2,500 – $7,000 |
| Injection foam insulation (whole house) | $4,000 – $9,000 |
| Interior wall soundproofing (per room) | $1,200 – $2,800 |
Can you insulate the walls of an Eichler without tearing them open?
Most Eichler walls are solid framing with no real cavity, so drill-and-fill isn’t possible. The practical options are exterior rigid foam during a re-skin or interior rigid foam during a remodel. Call (669) 215-4805 and we’ll map out what’s realistic for your home.
How long does wall insulation take?
A full drill-and-fill job in a typical Sunnyvale ranch home takes one to two days. Injection foam is similar. We’ll give you a straight schedule when you call (669) 215-4805.
Attic Cleaning & Rodent Proofing in Sunnyvale
Attic cleaning and rodent proofing in Sunnyvale handles the combination problem of rodent infestations in older ranch homes and Eichler attics, where the flat or low-pitch construction gives rats and mice easier access paths than steep roofs do. Once rodents get in, they tear up insulation, leave droppings everywhere, and chew wiring. We clean it out, sanitize, and seal every entry point as part of Attic Cleaning & Rodent Proofing, then install new insulation where the old stuff was too damaged to keep.
Attic Cleanout
Signs you need it
You hear scratching overhead at night, or you can see droppings and nesting material scattered across the attic floor.
What it costs in Sunnyvale
Attic cleanout in a typical Sunnyvale home runs $800 to $2,500 depending on contamination level.
How we do it
We vacuum out the contaminated insulation and debris with HEPA filtration, bag it, and dispose of it off-site.
Rodent Proofing & Exclusion
Signs you need it
Rodents return within weeks after every previous attempt, or you can see daylight around roof penetrations and gable vents.
What it costs in Sunnyvale
Rodent proofing and exclusion work in Sunnyvale typically runs $600 to $2,000 depending on entry points found.
How we do it
We inspect every roof penetration, gable, and eave edge, seal gaps with steel mesh and foam, and install protective covers over vents.
What Attic Cleaning & Rodent Proofing Costs in Sunnyvale
| Item | Typical range in Sunnyvale |
|---|---|
| Attic cleanout (moderate contamination) | $800 – $2,500 |
| Rodent proofing and exclusion sealing | $600 – $2,000 |
| Cleanout plus sanitizing and new insulation | $2,500 – $6,000 |
Does insulation need to be replaced after rodents?
Usually yes, if the contamination is heavy. Rodent droppings and urine soak into the insulation and it can’t be cleaned in place. We remove it, sanitize, and install new material. Call (669) 215-4805 for an honest assessment.
How fast can you get rodents out of my Sunnyvale attic?
Most exclusion jobs are completed in one visit, with sealing done the same day. The phone is answered by a live person 24/7, so call (669) 215-4805 and we’ll get you scheduled.
Home Energy Audit in Sunnyvale
A home energy audit in Sunnyvale gives you the full picture of where your ranch home or Eichler is losing conditioned air, which is rarely where homeowners assume it is. The audit includes blower door testing, thermal imaging, and insulation inspection to rank the fixes by dollar-per-comfort impact. We perform Home Energy Audit work for homeowners who want a prioritized plan, not a sales pitch, and the report is yours to keep whether or not we do any of the follow-up work.
Blower Door Test
Signs you need it
Your energy bills spike in summer, rooms feel uneven, or you’ve already insulated and the comfort problem didn’t improve.
What it costs in Sunnyvale
A standalone blower door test in Sunnyvale typically runs $250 to $500.
How we do it
We mount a calibrated fan in an exterior doorway, depressurize the house, and measure airflow in CFM at a standard pressure difference.
Thermal Imaging Inspection
Signs you need it
You want to see exactly which wall cavities are empty and where air is entering before spending money on insulation.
What it costs in Sunnyvale
Thermal imaging as part of an audit adds $150 to $400 in Sunnyvale.
How we do it
We scan walls, ceilings, and floors with an infrared camera while the blower door runs, then mark and photograph every anomaly.
What Home Energy Audit Costs in Sunnyvale
| Item | Typical range in Sunnyvale |
|---|---|
| Full energy audit with blower door and thermal imaging | $400 – $900 |
| Standalone blower door test | $250 – $500 |
| Insulation inspection only | $150 – $350 |
Is a home energy audit worth it before insulating?
Yes, especially for Sunnyvale homes where the heat problem is split across attic, walls, and roof deck depending on construction type. The audit tells you which fix to spend on first. Call (669) 215-4805 to book one.
Do I need a blower door test for a Sunnyvale permit?
Some Sunnyvale whole-home renovations trigger Title 24 requirements that include blower door testing. We can run the test and provide the documentation. Call (669) 215-4805 and we’ll tell you what your project needs.
Brands We Service in Sunnyvale
We install and service insulation from Owens Corning, Johns Manville, Knauf, and Rockwool, and we keep common replacement components on hand for faster turnarounds in Sunnyvale. If you know exactly what product you want, or you’re not sure which one fits your Eichler or ranch home, see our brands page for details.
Pricing for Insulation in Sunnyvale, CA
| Service | Typical range in Sunnyvale |
|---|---|
| Open-cell spray foam (per board foot) | $1.50 – $3.00 |
| Closed-cell spray foam (per board foot) | $2.50 – $5.00 |
| Full attic blow-in (standard ranch home) | $1,000 – $3,000 |
| Attic radiant barrier | $1,200 – $3,500 |
| Attic insulation removal | $1,500 – $4,500 |
| Full attic floor air sealing | $800 – $2,500 |
| Wall insulation (drill-and-fill, whole house) | $2,500 – $7,000 |
| Attic cleanout and rodent proofing | $800 – $2,500 |
| Full home energy audit | $400 – $900 |
Prices in Sunnyvale push higher when we’re working on an Eichler flat roof deck, when vermiculite or rodent contamination requires containment and disposal, or when an ADU or whole-home renovation triggers additional permitting. You’ll get a written, upfront price before work starts, and a free second opinion on any written estimate.
Neighborhoods We Serve in Sunnyvale
We work across Sunnyvale and have crews in the area most days, so scheduling is usually fast: same-week for most jobs, same-day for urgent attic or crawl space emergencies when capacity allows.
- Borregas
- Lakewood
- Heritage District
- Ponderosa Park
- Ortega Park
Service Area - Cities Near Sunnyvale
Walt’s Insulation serves Sunnyvale and the surrounding communities across the Bay Area’s western South Bay. If you’re in a neighboring city, you can reach the same live-answer team and schedule the same services: Mountain View, CA, Cupertino, CA, Los Altos, CA, and Milpitas, CA.
Serving Sunnyvale, CA - Our Local Coverage Area
We’re based in the Sunnyvale area and know this community well. Use the map below to see our service coverage - if you’re nearby, we can almost certainly help.
FAQs About Insulation in Sunnyvale
We carry crews in Sunnyvale most days, so standard jobs schedule same-week and emergencies often get same-day or next-day service. The phone is answered by a live person 24/7 at (669) 215-4805, not a voicemail or answering service.
Some jobs do, especially Eichler roof-deck spray foam, which requires a permit and plan review because the roof assembly changes. Attic blow-ins and air sealing usually don’t. We’ll tell you before you spend a dollar.
We do the work ourselves with background-checked, uniformed technicians. No subcontractors on insulation jobs. Walt’s is locally owned and owner-operated since 2000, with a published address and license number. Call (669) 215-4805 and ask for anyone on the team.
What happens when you call
- 1A real person answersNo phone trees - talk to a local insulation pro.
- 2You get an upfront price rangeHonest numbers before anyone is dispatched. No surprises.
- 3A background-checked tech heads outLicensed & insured, typically within 30-60 min.
- 4You approve before work beginsNothing starts until you say go.
What Sunnyvale Customers Say
"The house had rats in the attic insulation and a smell we could not place. Walt's crew pulled all of it, sealed the gaps where they were getting in, sanitized, and put in new blown-in. He sent photos of the sealed openings so I could see it done."
- Rosa Delgado"Spray foam in the garage ceiling under the bonus room. That room used to be unusable in summer. Walt talked me out of foaming the whole attic because it did not need it - saved me a couple thousand and I trust him more for it."
- Bud Larkin"Walt came out himself, stuck his head in the attic, and told me I had about four inches where I needed fourteen. No sales pitch, just the number and what it would cost to fix it. Crew was here two days later."
- Carl Meadows