Insulation Company in Ontario, CA
Blown in insulation is the most common retrofit we install in Ontario, and for good reason: the city’s 1950s through 1970s tract homes were built with R-11 batts at best, and many have settled or thinned to R-5 or less. Add hot inland summers that push attic temperatures past 150°F, and you get exactly the conditions where loose-fill cellulose and fiberglass earn their keep. We’re Aliso Viejo Insulation Co, and we’ve served Ontario since 2014 with blown-in, attic, and spray foam work matched to each home’s actual conditions. Call (877) 352-4780 for a free estimate.
Why Ontario Homes Are Different
Ontario’s housing stock splits into two clear eras. The 91761 and 91762 ZIPs hold mile after mile of mid-century single-story tract homes with low-slope roofs, unconditioned attics, and original insulation that was thin even by 1960 standards. The 91764 and south-side 1990s subdivisions were built to code-minimum fiberglass, which means 30 years of summer attic heat has degraded whatever R-value the builder installed. Neither era was designed for today’s cooling loads.
The climate is the other driver. Ontario sits deep in the Inland Empire, where July and August highs routinely top 100°F. Attic temperatures climb to 150°F or more, baking ductwork, cooking stored items, and radiating heat down through ceilings all evening. Insulation decisions here are less about winter heat loss and more about cutting cooling demand and keeping conditioned air inside the living space where you paid for it.
One thing we see constantly in the older tracts near downtown and along Holt Blvd: homes from the knob-and-tube era with empty wall cavities and attic ducts gone brittle from heat. The first insulation job on a 1950s Ontario house is often really a duct-sealing and attic air-sealing project with insulation as the final layer. Homeowners who skip the air-sealing step spend money on R-value that leaks straight through gaps.
Our Main Ontario Services
Most Ontario homeowners reach out to us about two situations: attics that need a full re-insulation and homes that would benefit from spray foam’s air-sealing and R-value. Both are covered here.
Attic Insulation in Ontario
Attic work in Ontario usually means removing and replacing degraded fiberglass, air-sealing every penetration, and bringing the attic to R-38 or R-49 depending on the home and budget. The 150°F attic problem makes this the single highest-impact insulation job for comfort and cooling bills. We offer Attic Insulation in Ontario as a dedicated service with full details on the local approach.
Spray Foam Insulation in Ontario
Spray foam makes sense in specific Ontario situations: attics with HVAC equipment and ducts in the conditioned envelope, crawlspace conversions, and rooms where air leakage is the real culprit. Open-cell handles sound and air sealing in wall cavities; closed-cell adds R-value and moisture resistance where attics get punishingly hot. Read more on Spray Foam Insulation in Ontario and how we deploy both Icynene and Demilec systems there.
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.
Blown In Insulation in Ontario
Blown in insulation is the workhorse retrofit for Ontario’s older homes because it can fill every irregular cavity without disturbing walls or ceilings. In the 1950s through 1970s tracts where original R-11 batts have settled to half their labeled value, blowing loose-fill fiberglass or cellulose over the top is the fastest, least invasive way to reach a true R-38 or better. When the attic hits 150°F, a continuous blanket of loose fill keeps that heat from bleeding down through the ceiling into your living room. Our Blown In Insulation service covers the full range of materials and methods.
Cellulose Insulation
Signs you need it
Your energy bills climb every summer while rooms directly under the attic stay hot until midnight, and existing attic batts look thin, discolored, or compressed.
What it costs in Ontario
Blown cellulose runs $0.60 to $2.30 per square foot installed in Ontario.
How we do it
We run a hose into the attic, blow GreenFiber recycled cellulose to the specified depth, and leave a uniform blanket that fills around framing, vents, and odd corners.
Blown In Attic Insulation
Signs you need it
You can see the tops of ceiling joists in your attic, or your attic temperature climbs so high that duct insulation looks cracked and dry.
What it costs in Ontario
Blown in attic insulation typically lands between $1,200 and $3,500 for a standard 1,500 square foot Ontario attic, depending on material and R-value target.
How we do it
We seal penetrations and any duct leaks first, then blow loose fill to a full R-38 or R-49 across the entire attic floor, including over existing partial batts where safe.
What Blown In Insulation Costs in Ontario
| Item | Typical range in Ontario |
|---|---|
| Blown cellulose installation | $0.60 – $2.30 per sq ft |
| Standard attic blow-in job (1,500 sq ft) | $1,200 – $3,500 |
| Duct sealing / air sealing add-on | $400 – $1,200 depending on attic size |
Prices in Ontario shift based on how much old insulation must be removed first, whether the attic has knob-and-tube wiring that must be insulated around, and how many recessed can lights need boxing. We give upfront quotes before any work starts, and the number we quote is the number you pay.
Can blown in insulation be added over old insulation in Ontario?
Yes. Blown cellulose or fiberglass can be installed directly over existing batts as long as the old material is dry and no knob-and-tube wiring is exposed in contact with it. We inspect before quoting. Call (877) 352-4780 for a free attic assessment.
How long does blown in insulation last in an Ontario attic?
Blown cellulose and fiberglass last 20 to 30 years in Ontario conditions if the attic stays dry and vermin-free. Settling reduces R-value slowly over time, which is why we check depth during every service. Call (877) 352-4780 to schedule an inspection.
Brands We Service in Ontario
We install and service insulation from eight manufacturers, with GreenFiber cellulose, Owens Corning and Johns Manville fiberglass, and Knauf materials most common in Ontario attics. Parts and material are sourced quickly, so most Ontario blow-in jobs are scheduled within days, not weeks. See our brands for the full lineup.
Pricing for Insulation Company in Ontario, CA
| Service | Typical range in Ontario |
|---|---|
| Blown cellulose installation | $0.60 – $2.30 per sq ft |
| Standard attic blow-in job (1,500 sq ft) | $1,200 – $3,500 |
| Blown in attic insulation (full removal + new) | $1,800 – $4,200 |
| Blown in fiberglass insulation | $0.80 – $2.50 per sq ft |
| Blown in cellulose insulation (new construction) | $0.70 – $2.00 per sq ft |
| Loose fill insulation | $0.60 – $2.30 per sq ft |
| Duct sealing / air sealing add-on | $400 – $1,200 depending on attic size |
Two things push Ontario prices upward: first, the older tracts along Holt Blvd and near downtown often have original insulation that must be vacuumed out before new material goes in, and second, attic air-sealing is a necessary add-on that many homeowners skip only to regret it later. Every quote from us is upfront and itemized with no hidden charges.
Neighborhoods We Serve in Ontario
We work across Ontario’s residential grid, from the mid-century tracts west of the 15 to the newer subdivisions south of the 60 and east toward the 10. Our crews know which home era they’re walking into based on the street grid, and that speeds up both quoting and installation.
- Downtown Ontario (91761)
- North Ontario (91762)
- South Ontario (91764)
- East Ontario near the 10 (91758)
- Archibald Ranch / newer south tracts (91761)
For most Ontario neighborhoods, we can schedule an estimate within 48 hours and start standard attic blow-in jobs within a week.
Service Area – Cities Near Ontario
Our Ontario crews also cover the neighboring Inland Empire communities with the same eight-brand material access and upfront pricing. That includes Montclair, CA to the northwest, Upland, CA at the foothill base, Chino, CA to the southwest, and San Antonio Heights, CA above Upland. If you’re on the edge of any of these cities, call and we’ll confirm coverage.
Serving Ontario, CA — Our Local Coverage Area
We’re based in the Ontario 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 Company in Ontario
We typically schedule estimates in Ontario within 48 hours and can start standard attic blow-in or spray foam work within a week. Emergency attic situations, like storm or vermin damage, get priority scheduling. Call (877) 352-4780 to check current availability.
Most attic and wall retrofits in Ontario don’t require a permit, but spray foam in certain locations or homes in historic zones may need city sign-off. We confirm permit requirements for every job before work starts and handle the process when needed.
Yes. We cover all Ontario ZIPs including 91764, 91798, 91758, and 91761, plus nearby cities like Montclair, Upland, Chino, and San Antonio Heights. If you’re unsure whether we serve your street, call (877) 352-4780 and we’ll confirm immediately.
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 1-hour.
- 4You approve before work beginsNothing starts until you say go.
What Ontario Customers Say
"Plastic laid from the front door to the attic hatch and they vacuumed the hallway afterward."
— Brooke Pruitt"Told me the crawlspace didn't need doing and only the attic did. Half the job, half the money."
— Marcy Anderson"Found and sealed a gap around the chimney chase that was basically an open chimney to the attic."
— Sanjay Patel