Spray Foam Insulation in Janesville, WI

Find top-rated spray foam contractors and save up to 37% on energy bills

Compare 5 verified spray foam insulation contractors serving Janesville, Wisconsin, backed by 201 customer reviews averaging 4.9★. Whether you're insulating a new build, retrofitting an existing home, or upgrading attic and crawl-space insulation, these pre-screened Janesville contractors handle both open-cell and closed-cell spray foam. Homeowners here typically cut energy bills by around 37% — get free quotes and read verified reviews below.

💰 Estimated Energy Savings in Janesville

37%
Average Energy Savings
Typical range: 32% - 42%
$1,732
Estimated Annual Savings
Based on $390/month average energy cost
4 years
Average Payback Period
Return on investment timeline

Note: Actual savings vary based on home size, current insulation, energy rates, and climate conditions. These estimates are based on Department of Energy data for Very Cold.

Verified Contractors in Janesville

5⭐
22 Google reviews

Recent Reviews:

Daniel Miralles★★★★★3 weeks ago

We bought a Cape Cod style house in a few years ago and soon found out it was poorly insulated. I found out that Cape Cod style houses are one of the most difficult types of houses to insulate due to the many voids that are built into the construction. The house also needed a new roof so after researching spray foam insulation and talking to Brad the owner of Weather Seal Insulation and Roofing I decided it would be the best option. Weather Seal is one ,of the few companies that does both roofing and spray foam insulation. The advantage of which benefited us because while they were tearing off the old roof they discovered that the gable at the front of the house and over part of our living room, had no insulation. Brad was able to quickly come and spray foam that space so the roofers could continue their work. Now our living room is much warmer. Another advantage of spray foam insulation applied to the underside of the roof deck is that the insulation on the attic floor can be removed, which we had done, providing easy access to electrical wiring if it needs to be repaired or upgraded. When inspecting our house for a quote, Brad suggested spray foaming the basement walls, because a significant amount of heat is transferred through the walls. I was skeptical at first, but after thinking about it, it made sense, and with the added coat of protective white paint over the spray foam, I would brighten up the basement which needed to be painted anyway. Now my basement is the warmest level in the house, and the basement looks cleaner and brighter. Even my father in law, who has many years experience in the construction trades, was impressed at how well it looked. The whole house is noticeably warmer and the furnace comes on less often.

Bill McClure★★★★★2 months ago

Brad was given a near impossible task after another contractor left me high and …wet… (insulation). After multiple walkthroughs to make sure he covered every scenario, and ensuring he had a step by step plan, his team executed a near flawless job. Incredible communication, incredible work ethic, and willing to go above and beyond to make sure I was happy. Count yourself lucky if you get the chance to work with Weatherseal and Roofing. Thanks again, Brad!

Linda Michaelson★★★★★5 months ago

I am a Single Woman owning a home and found rodent damage on my roof. Upon searching for Roofing Repairs, Weather Insulation and Roofing Called back came right away after holiday weekend and came over at 6:45pm and stayed until repair was done. Then he found things that when I had roof installed they failed to do during insulation and also took the time to take care of that. I am amazed with this Company and Highly Recommend using this service. Brad I thank you for all your honesty and extra mile you took for me. I will call you if needing repair again for sure. Thank You

5⭐
3 Google reviews

Recent Reviews:

Shawn Uschan★★★★★a year ago

I just worked with this company. Great group of guys, who actually care about their work and reputation. I would recommend this group to my mother 100%.

Richard J★★★★★4 years ago

Great company to work with, at very fair price. Cliff and his men have the expertise and equipment to troubleshoot and air seal and insulate hard to reach attic areas.

Randy Zwieg★★★★★4 years ago

5⭐
28 Google reviews

Recent Reviews:

thomas simonsen★★★★★7 months ago

I just had them spray the inside of my 12'x16' cabin in the woods. They did the walls, ceiling, and floor joists (2x4).Everything from their timeliness to replying to my initial inquiry, arranging to see my project, getting me a bid, getting me on the schedule, and getting my project completed was nothing short of a pleasure. They kept me informed the whole time from start to finish. The gentleman that did the spraying was very meticulous and was careful to get every nook and cranny. When they were done, they did an excellent job of trimming the excess, caulking between all of the studs, floor, and top wall plates. They also did an excellent job cleaning up because this process does make a bit of a mess. I was really surprised at how much spray foam solidifies a structure! When they were done, I set up a lazer to start finishing the ceiling and when I walked around, the lazer line didn't move at all! My cabin sits on concrete blocks so it's not real sturdy to begin with but it feels really solid now. I'm in the trades myself and I firmly believe that you get what you pay for and I feel like I got what I paid for and I'm very happy with the job that was done. You can tell in the first 5 minutes of meeting any employee that they take pride in their work and it shows. Thanks a lot to everyone at Rock Road!

hunter. GoPro★★★★★6 years ago

I first called Rock Road Company after another spray company that I had lined up had backed out of spraying my house the day before it was supposed to be sprayed. I explained to Carrie my situation along with the tight time line that I had for spraying before my drywall installers were scheduled to do their job. Carrie and Luyk made it a point to go out of their way to come measure my project the day after I called. Rock Road Company was out to my house spray foaming the very next week! The Rock Road crew was very knowledgeable and experienced. They did an excellent job prepping, spraying and cleaning up everything in my house. I will for sure be keeping their number in my contacts for future projects and referring them to anyone that is interested in spray foam. Thank you again Rock Road Company!

Michael★★★★★4 years ago

At first, I was skeptical about foam insulation for my building due to the perceived high cost. When I contacted Rock Road, they immediately set up an appointment, to which they followed up promptly. While my initial reaction to the bid was that it was high (as I expected,) Luyke and Carrie explained in detail all of the cost aspects of a foaming project. They explained the benefits of foam insulation in detail, which helped me understand the long term value of foam versus fiberglass or blown insulation. I decided to go with them. The crew payed high attention to preparing the job site with thorough masking to ensure all surrounding areas, appliances and fixtures are protected before beginning the spray. The prep work took up the majority of the time, far more than the actual spray (which was fascinating!) The Rock Road crew took tremendous care in their job clean-up; in fact, I was surprised that the clean up took nearly as long as the prep work and was impressed that there was not one spot of foam on a surface it wasn’t intended to be on. Upon completing their work, I was blown away that the final invoice was less than the initial quote. Carrie explained that they plan and bid for every issue and problem, seen and unseen. They do not want the customer surprised with additional costs. If the job goes smoothly with no hidden issues, Rock Road reduces the final invoice. They are more than fair. My experience with Rock Road far exceeded my expectations. I’ve had one year under my belt and I have to say my building is a giant YETI cooler! It took such a small amount of energy to heat and cool the structure that I saved a ton in fuel costs. It is also extremely quiet. The big picture of foam insulation is now clear to me. I highly recommend the Rock Road Company and will use them again in the future.

4.9⭐
75 Google reviews

Recent Reviews:

R S★★★★★3 weeks ago

I've had Ryen and his team out to upgrade my bathroom fan and properly vent it though the roof, resolve some mold in the attic, and do an insulation and ventilation upgrade in the attic and they've done a great job every time. They we're responsive and quick to schedule. When giving a time when they'd show up I was given a specific time instead of a half-day window and when they finished for the day they always cleaned up before leaving. I didn't get competing quotes for the smaller jobs but the price for the larger project was slightly higher than other quotes with the caveat that they were not one to one quotes. One of the differences being that Ryen did some actual construction work while the others wanted to just use foam blocks and the more permanent solution and quality was worth the cost. I'll plan to use them again when I have more insulation or ventilation work done in the future.

Leonard DeMontigny★★★★★a year ago

Ryen and his crew completed the job in a timely manner. Both him, and his crew were very professional and courteous. They cleaned up after themselves every time they were finished for the day. The quality of their work was excellent. I would highly recommend Accurate Insulation Solutions LLC to all people looking for quality workmanship at a fair price. Thank you.

Mary Sucich★★★★★5 months ago

Ryen and Crew were exceptional. They were very very professional and got the job done in time frame they stated. The cleaned up after the work was done and we could not have been happier. I would recommend them to anyone and you would not be disappointed.

4.7⭐
73 Google reviews

Recent Reviews:

Martha Howell★★★★★2 weeks ago

Aaron and Louie came today and insulated the attic in my 1955 home. They did an excellent job, and the house is already feeling less drafty! They were very thorough, helpful, respectful of my house, cleaned up, and even dealt with my bratty cat doing her best to climb into the attic. Every contractor I have talked with recommends Rockweiler, and I am very pleased with their work.

Chris Davidson★★★★★a month ago

I had the attic insulation in our 25 year old home beefed up and air sealed to exceed min code. Everyone at Rockweiler was a pleasure to work with. From the highly detailed no pressure sales consultation, the scheduling process, the excellent work and detail of the crew I could not be happier. This company clearly cares about quality and treat your home with care. Thank you!

Lynette Gebben★★★★★4 weeks ago

After removing all previous insulation, we had soffits and attic insulated. Our recessed lighting was sealed and R60 insulation was installed. Since was we’re doing a whole house remodel, they were flexible on timing and fit us into the schedule on our time frame. They had competitive pricing and professional service.

Frequently Asked Questions — Spray Foam Insulation in Janesville

These are the questions Janesville homeowners ask most about spray foam cost, R-value, and open- vs. closed-cell foam — with context for local pricing and roughly 37% typical energy savings. Compare the 5 verified Janesville contractors above for exact quotes.

Why is spray foam insulation especially important in cold climates like Janesville?▼
In cold climates like Janesville, WI, proper insulation is critical to preventing heat loss, ice dams, and frozen pipes. Spray foam's air-sealing properties stop the cold air infiltration that traditional insulation cannot address. It also prevents the moisture buildup inside walls that leads to mold in cold-weather freeze-thaw cycles. Homeowners in WI typically save 25–35% on heating costs. Note: in tightly sealed homes, proper mechanical ventilation is commonly recommended to maintain fresh air exchange without losing the heat you've paid for.
Does spray foam insulation prevent ice dams in Janesville?▼
Yes — spray foam insulation is one of the most effective solutions for preventing ice dams in cold climates like Janesville, WI. Ice dams form when heat escapes through a poorly insulated attic, melting snow that refreezes at the eaves. By creating an air-tight thermal barrier in the attic, spray foam eliminates the heat loss that causes ice dams in the first place.
What R-value do I need for spray foam insulation in Janesville?▼
For cold climates like Janesville, WI, the Department of Energy recommends attic insulation of R-49 to R-60. Closed-cell spray foam provides R-6 to R-7 per inch, meaning 8–10 inches achieves code-minimum performance. Open-cell foam at R-3.5 per inch requires greater thickness. A local contractor familiar with WI building codes can recommend the exact specification for your home.
Is spray foam insulation worth the cost?▼
For most homeowners, yes. Spray foam creates an air-tight seal that traditional insulation cannot match, reducing energy bills by 15–35% annually. It also adds structural rigidity, acts as a moisture and vapor barrier, reduces outside noise, and can increase home resale value. The higher upfront cost compared to fiberglass is typically recovered within 3–7 years. One important note: because spray foam creates a very tight building envelope, proper mechanical ventilation is important to maintain healthy indoor air quality and prevent interior moisture buildup. This is typically handled by an Energy Recovery Ventilator (ERV) — a system that brings fresh outside air in while pushing stale air out, recovering the energy from the outgoing air so you don't waste what you paid to heat or cool — or a Heat Recovery Ventilator (HRV), which works similarly but is optimized for cold climates. A qualified contractor will assess whether your home needs ventilation upgrades as part of the installation.
How much does spray foam insulation cost in Janesville, WI?▼
In Janesville, WI and the surrounding area, spray foam insulation typically costs $1.00–$3.00 per square foot installed, depending on the type and your home's specifics. Open-cell foam runs $0.44–$0.65 per board foot, while closed-cell foam costs $1.00–$2.00 per board foot. A typical 2,000 sq ft home attic in Janesville costs $2,000–$6,000. Most Janesville homeowners recoup this investment within 3–7 years through energy savings of 15–35% annually.
What is the difference between open-cell and closed-cell spray foam?▼
Open-cell spray foam is softer, less dense, and less expensive. It expands significantly and is ideal for interior walls, attics, and soundproofing. Closed-cell spray foam is denser, stronger, and provides a moisture barrier — making it better for exterior applications, crawl spaces, and areas prone to flooding or humidity. Closed-cell also has a higher R-value per inch (R-6 to R-7 vs R-3.5 to R-4 for open-cell). One key difference: open-cell foam allows some vapor movement, while closed-cell acts as a vapor barrier — an important consideration for your home's ventilation needs.
How long does spray foam insulation last?▼
Spray foam insulation is one of the most durable insulation options available, with a lifespan of 80+ years when properly installed. Unlike fiberglass batting which can sag and settle over time, spray foam maintains its shape and insulating properties indefinitely. It will typically outlast the building it is installed in.
How do I find a qualified spray foam insulation contractor in Janesville, WI?▼
When searching for a spray foam contractor in Janesville, WI, look for ones who are licensed, insured, and have verifiable reviews. Spray foam requires specialized equipment and training — improper installation can cause off-gassing, adhesion failure, or fire hazards. Ask for references, verify their insurance, and get at least 2–3 quotes. A qualified Janesville contractor will also assess your home's ventilation needs — a tightly sealed spray foam installation requires adequate mechanical ventilation to prevent moisture and indoor air quality issues. FoamMatch pre-screens all listed contractors in Janesville for licensing and insurance so you can compare verified professionals in your area.
How long does spray foam installation take?▼
Most residential spray foam jobs take 1–2 days depending on the size of the area. A standard attic takes 4–8 hours. After spraying, the foam cures within 24 hours, though most contractors recommend waiting 24–72 hours before occupying the space due to off-gassing during the curing process.
Does spray foam insulation need to be replaced?▼
No — spray foam insulation does not need to be replaced under normal circumstances. Unlike fiberglass insulation which degrades over time, spray foam maintains its R-value and air sealing properties for the life of the building. The only reasons to remove or replace spray foam are water damage, renovation work, or improper original installation.