Boulder Insulation › Blown-In Insulation
Blown-In Insulation in Boulder, CO
In Boulder, Mapleton Hill Victorians, Whittier bungalows, University Hill rentals, thin attic insulation bakes upstairs under high-altitude sun. Blown-in restores even, full-depth coverage to the rated R-value.
- Free attic depth inspection
- Itemized quote, no pressure
- Xcel rebate guidance
Your Front Range crew
Based in Commerce City, serving Boulder and the metro
Where does your attic actually stand?
Attic R-value depends on even depth across the whole floor, and Boulder’s older homes especially tend to have wind-washed, thin coverage near the eaves where chinook gusts have scoured loose-fill away over the years. Zone 5B’s target of R-49 to R-60 is hard to hit with patchy, decades-old insulation, no matter how thick it looks in the middle of the attic.
- Measured during free inspections across Boulder housing stock. Your exact number comes with your assessment.
TRUSTED PRODUCTS & PARTNERS
The Brands Behind Every Grizzly Install
Every Boulder attic we insulate uses recognized cellulose or fiberglass loose-fill, no unlabeled material, no guesswork, just building materials with a known track record.
01THE PROBLEM
The Attic Problems Blown-In Insulation Quietly Solves.
Boulder’s building stock runs from century-old Mapleton Hill and Whittier homes to mid-century ranches near Table Mesa, and most of them were insulated once, decades ago, and never touched again. Add Boulder’s intense summer solar gain and the periodic chinook downslope winds that can hit 60+ mph, and any thin or wind-disturbed spot in the attic becomes a real energy leak. It’s rarely the furnace or AC struggling, it’s usually under-depth, settled loose-fill combined with air leaks around can lights, chimney chases, and the attic hatch. The house is telling on its insulation, not its equipment.
A · Attics still sitting at an old R-19 to R-30
Bonus rooms and home offices framed above an attached garage sit over unconditioned space, so heat drains through the floor while the garage pulls it away below. You get cold floors, a room running 10–15° off the rest of the house, and a furnace that never catches up. We insulate the floor joists, knee walls, and sloped ceilings, then air-seal the garage ceiling and rim.
B · Loose-fill that has settled, thinned, or gone flat
Most Boulder basements, the brick ranches east of Wadsworth, the split-levels around Lake Arbor, have bare concrete or block foundation walls. Finishing that basement without insulating the walls first buys you a cold, clammy room and a heating bill to match. Blown-Ins in the new stud walls, with the correct vapor retarder, turn it into comfortable, usable square footage.
C · Bare patches, gaps, and wind-washed eaves
Additions, pop-tops, and finished attic conversions are often framed to the minimum of their day, or never insulated in the walls at all. That leaves one part of the house always chasing the thermostat. Filling the wall, floor, and rafter cavities with properly sized blown-in insulation brings the new space up to the same comfort as the original home.
D · Ice dams and a top floor that never holds heat
Insulation isn’t only about temperature. Blown-Ins packed into interior walls and between floors cut the sound that travels between a media room and the bedrooms, an office and the living room, or upstairs and down. Mineral wool does this best. It’s a small add during a remodel that quietly changes how the whole house feels.
02THE FIX
Cellulose or Fiberglass. One Honest Recommendation.
We inspect the attic in person first, measuring real depth, checking for wind-washing near the eaves, and finding air leaks, before recommending anything. Air-sealing and eave baffles go in first to protect against chinook wind intrusion, then we recommend cellulose for dense, borate-treated coverage in older Boulder attics or fiberglass where settling resistance matters more. It’s one honest recommendation based on your specific attic.
03WHAT TO EXPECT
A Half-Day Inside. Here's How It Goes.
A typical Boulder blown-in job runs from initial inspection through air-sealing to the final depth-check in a few hours, whether it’s a Mapleton Hill Victorian or a Table Mesa ranch.
We confirm the plan from your assessment, then protect floors and finishes around the work area.
We air-seal top plates, can lights, and the attic hatch, then set baffles at the eaves so airflow cannot wind-wash the new insulation.
Loose-fill is machine-blown evenly across the attic floor to the marked depth, filling every gap around joists, ducts, and penetrations.
We check coverage against depth-ruler cards staked across the attic so you hit the rated R-value corner to corner.
We vacuum up, haul away offcuts, and walk every cavity with you before we leave.
The Grizzly 100% Guarantee
If the work isn't right, we make it right. That's the reputation we've built across the Front Range, and it's our only sales pitch.
04COST & SAVINGS
What Blown-In Insulation Costs in Boulder
Pricing varies job to job based on your attic’s square footage, how much depth is needed to reach target R-value, the amount of air-sealing required, and whether old, wind-compacted, or moisture-affected insulation needs to come out first. You’ll see an itemized quote before any work starts.
Attic square footage
The attic floor area we cover to target depth
Current attic R-value
How far your attic sits below the Zone 5B target
Air-sealing & baffles
Top plates, can lights, hatch, and eave baffles
Removal needs
Only if material is soiled or damaged
Three ways the net cost drops
Xcel Energy rebates
Qualifying insulation + air-sealing upgrades earn utility rebates across Boulder. We flag what applies in your estimate.
Federal 25C tax credit
30% of qualifying insulation costs, up to $1,200 per year, under the Inflation Reduction Act.
Lower bills, every month
Heating and cooling dominate Front Range energy bills, and unconditioned walls and floors are among the highest-impact upgrade point in most Boulder homes.
★ ★ ★ ★ ★
The upstairs bedroom in our Whittier bungalow was unlivable by early afternoon every summer, and every winter we'd get ice dams after the first big chinook-driven snow. Grizzly sealed the leaks around our old knob-and-tube wiring penetrations and topped off the attic, and the difference this winter was immediate, no more icicles, and the upstairs stays warm without the furnace running constantly.
D
David R.
05QUESTIONS
Blown-In Insulation in Boulder, Answered Straight
Prefer to just ask?
Call the team that will actually be working in your attic, (303) 854-6221, for a free, no-pressure assessment of your Boulder home.
Blown-in insulation is loose-fill cellulose or fiberglass machine-blown into the attic to a measured, even depth. In Boulder it’s used on attic floors in everything from Mapleton Hill Victorians to Table Mesa ranches, filling gaps around obstructions and topping off insulation that’s settled or thinned with age.
Both materials work well installed correctly, but Boulder’s older homes often lean toward cellulose for its dense, borate-treated coverage in irregular, century-old attic framing. Fiberglass is a strong choice where settling resistance or moisture tolerance near a bath fan matters more. We’ll tell you which fits your attic after we’ve actually looked at it.
Yes, in most cases we blow new insulation directly over existing material without removing it, as long as it’s dry and reasonably clean, common in Boulder’s older homes where the original insulation has just settled over decades. If there’s been water intrusion or the existing material is soiled, we’ll remove that portion first.
Boulder sits in Climate Zone 5B, which calls for attic insulation of R-49 to R-60, roughly 14 to 17 inches of cellulose or 16 to 20 inches of fiberglass depending on the product. We measure actual depth across the whole attic rather than assuming it’s uniform, since older Boulder attics rarely are.
Cellulose settles somewhat after installation and we account for that when we install it, but ongoing settling isn’t the only issue, Boulder’s chinook winds can wind-wash loose-fill away from eaves over time if the attic isn’t properly baffled and air-sealed. That’s why we address air leaks and install eave baffles alongside any top-off, not just add more material on top of the problem.
Blown-in makes the most sense for Boulder’s attic floors, especially in older homes with irregular framing or existing insulation to build on. Batts fit open wall cavities better than attics. Spray foam can work for complex Boulder rooflines or conditioned attic spaces, but for a standard vented attic, blown-in gets you to R-49–R-60 without the added cost.
06EVERY COMMUNITY WE SERVE
Blown-In Insulation Near Boulder
BoulderAuroraBrightonBroomfieldCentennialColorado SpringsCommerce CityDenverFort CollinsGreeleyHighlands RanchLakewoodLittletonLongmontLovelandParkerThorntonWestminster
07GET STARTED
Find Out How Much Heat Your Attic Is Losing.
Every job comes with our 100% guarantee.
- (303) 854-6221 · Mon–Sat 8 AM–5 PM · Sun by appointment
- info@grizzlyinsulationco.com, fast replies, usually same day
- 7140 Ivy St Unit B, Commerce City, CO 80022, 10 miles from Boulder
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