Insulation Contractor in Corona, CA - Cooler Rooms Upstairs and Sealed Attics
Premium Wildomar Spray Foam Insulation is an insulation contractor working in Corona, CA. We seal and insulate attics, walls and crawl spaces, top up thin blown-in, pull out old or dirty insulation and spray foam where it fits.
- Licensed and insured.
- Free in-person estimates.
- We respond within 1 business day.
Corona houses as we find them on jobs
We're an insulation contractor based in Wildomar, where I started this business in 2013, and Corona is the farthest north of the cities on this site, up the 15 past Temescal Valley. It was a citrus city long before the tracts went in, so the calls we get there come from both ends of that story, older houses closer to the middle of town and newer homes built out farther.
That mix changes what we find up top. Older houses usually have thin, settled insulation and plenty of gaps around pipes and wiring, while newer ones tend to have a fair layer that was never sealed underneath and a room over the garage that runs hot.
Insulation work we do in Corona homes
Spray foam insulation
Spray foam suits the room over the garage and attics where the ductwork runs, because it seals air and insulates in one pass, though it costs more.
Attic insulation
Most Corona calls start in the attic, where we measure what's up there, seal the gaps, then bring the edges up as deep as the middle.
Blown-in insulation
Blown-in, loose fill sent through a hose, is how we top up the thin, settled layers we find in older Corona houses without tearing anything out.
Home insulation
When the whole house feels drafty or the power bill keeps climbing, we look at the attic, walls and floors together and fix them in the right order.
Insulation removal
If the old insulation is soaked, matted or full of droppings, we pull it out first, because new material laid over it just keeps the problem.
Crawl space insulation
Corona houses with a crawl space often come with cold floors, so we insulate under the floor once we've checked the space for water and loose wiring.
Wall insulation
Some older Corona houses have walls with little or nothing inside them, and we fill those through small openings instead of tearing the whole wall open.
Air sealing services
Air sealing, closing the gaps before insulating, covers the whole house, around doors, outlets, plumbing and the garage wall where drafts get in.
Basement insulation
Where a Corona house has a basement, we insulate its walls so the space stays drier and takes less to keep comfortable through the year.
Closed-cell foam insulation
Closed-cell foam, a dense foam that blocks moisture, fits crawl spaces and tight spots where a thin layer has to do a lot of work.
Open-cell foam insulation
Open-cell foam is softer and lighter, so we use it on attic rooflines and walls where you want the air sealed but don't need a moisture barrier.
Commercial insulation
Building owners in Corona call us for offices, shops and warehouses, and I walk the building first so the work gets planned around how it's used.
Crawl space vapor barrier
A plastic vapor barrier laid over the crawl space dirt keeps ground moisture out of the framing and the insulation sitting above it.
Vapor barrier installation
We put vapor barriers on walls and floors where moisture would work into the insulation, and leave them out where they'd trap it instead.
Attic air sealing
Before we add anything to a Corona attic, we seal around can lights, pipes and the hatch, because insulation over open gaps still leaks air.
Retrofit insulation
Retrofit work adds insulation to a finished house without gutting it, which suits older Corona homes you're still living in while we work.
Get a free on-site insulation estimate in Corona
Send the form and we'll get back to you within one business day to set a visit. I come out myself, the estimate's free, and there's no pressure and no obligation to go ahead.
- Based in
- Wildomar, CA 92595
- Hours
- Mon–Fri: 6 AM–11 PM, Sat–Sun: 8 AM–9 PM
Permits, licenses and what we check in Corona
In Corona, building, electrical, mechanical and plumbing permits come from the city's Planning & Development department, and if your job needs one, that step sits ahead of the work, so it can move the start date more than our crew does. Before you hire anyone, you can check that they hold a license from the California Contractors State License Board and a Corona business license. I check the permit step with the city for your address, and when one's needed we file it and keep you posted.
The price turns on the same things here as in Lake Elsinore, how big the attic is, how many inches are already up there, whether old insulation has to come out and how many gaps need sealing. The schedule turns on the permit step and on anything that has to be fixed first, like a roof leak or a bad wire, because I'd rather fix it than bury it under new insulation. Your own figure comes from the estimate.
Why Corona attics end up needing work
Most calls we get start with a hot room upstairs, a room over the garage nobody wants to sit in or a power bill that keeps going up. In older houses the insulation has usually settled thin and the gaps around lights and pipes were never closed, and sometimes it's been soaked or nested in, so we pull that out before anything new goes down. In newer houses the layer is often fine in the middle and thin at the edges, which is backward, so we even it out and keep the eave vents clear so the attic can still breathe.
The city lists construction rules for fire hazard severity zones that apply to some properties, so if your house falls under them, we check those rules before we change anything around the vents.
How a Corona insulation job runs, start to finish
Here's how a job in Corona goes from your first call to the walk-through, and where the city's schedule fits in.
Call or send the form
You call (951) 417-1017 or send the form, and we get back to you to set up a visit. Someone needs to be home so I can get into the attic or crawl space.
I look at the space
I come out myself, get into the attic, walls or crawl space and see how many inches are up there and what shape it's in. Before I leave you know what I'd do, what has to be fixed first and what I'd skip, so you're not guessing about cost.
Permit and inspection, if needed
When there's a permit, the city books inspections Monday through Thursday, and a Friday inspection is only for an unusual situation or hardship, called in by Wednesday at 5 p.m. City Hall is closed Fridays, so we plan the work around that week.
Seal, insulate, walk through
Our crew seals around lights, pipes and the hatch before any insulation goes down, and keeps the eave vents open. When we're done, I walk the finished space with you.
Questions about insulation in Corona
How do I find out if my attic insulation job needs a permit in Corona?
Call the city's permit line at 951-736-2250, which is the place to ask whether your job needs one. If you'd rather not make the call, we check it for your address when I plan the job.
Does an insulation contractor from Wildomar need a business license to work in Corona?
Yes, Corona requires a business license of every business working in the city, whatever the trade and even when the main address is somewhere else, like ours. Licenses renew every year on their anniversary, so it's fair to ask any contractor whether theirs is current.
When does a contractor need a California license for insulation work?
A contractor needs a state license when the job needs a building permit, uses any hired workers, or comes to $1,000 or more in labor and materials. The small-job exemption went from $500 to $1,000 in 2025 and only covers work with no permit and no hired help, so nearly any attic job with a crew calls for a licensed contractor. We're licensed and insured.
What building code does Corona use for insulation work?
Corona has adopted the 2025 edition of the California Building Standards Code, by an ordinance the City Council adopted in November 2025. That's the code we plan permitted work around in Corona.
What affects the cost of attic insulation in Corona?
The size of the attic, what's already up there and how much sealing it needs set most of the price. Old insulation that's soaked or dirty has to come out first, and foam costs more than loose fill. For most attics, sealing the gaps and topping up with blown-in is the better buy, unless your ductwork runs up there, where foam earns its cost.
How long will the crew be in my attic, and do we have to leave the house?
For blown-in and air sealing you can usually stay home while we work, but with spray foam you, the kids and the pets stay out until the re-entry time, the wait after spraying before anyone comes back in. How long we're up there depends on the attic's size and whether old material comes out first, and I'll tell you both at the visit.
Ask about your Corona insulation job
Call (951) 417-1017 or send the form, and I'll tell you plainly whether your attic needs work at all or needs something else fixed first.