⭐⭐⭐⭐⭐ Trusted by Denver-area homeowners · 150+ insulation projects completed
Insulation Contractors in Boulder, CO
From the 1890s Victorians of Mapleton Hill to the mid-century ranches of Table Mesa and the newer builds out in Gunbarrel, one certified local crew handles your attic insulation, air sealing, and rodent defense — and backs every job with a 100% guarantee.
- Free, itemized estimates
- Financing available
- Most attics done in 1–2 days
- Serving Boulder, CO and all of Jefferson County
Get Your Free Boulder Estimate
Takes 30 seconds. We reply within 24 hours, no pressure, no spam.
1–2 Days
Most Projects Completed
R-49–R-60
Climate Zone 5B Attic Target
150+
Insulation Projects Completed
5 ZIPs
All of Boulder Covered
- Insured & Certified
- 100% Guarantee
- Free Estimates
- Locally Owned · Commerce City, CO
INSULATION COMPANY ARVADA, CO
Insulation Built for Boulder's Wind and Its 140-Year Housing Stock
Boulder is a city of strong opinions about energy — with a housing stock that spans 140 years. A single block can hold an 1890s Victorian near Pearl Street, a Craftsman in Whittier, a student rental on University Hill, and a 1950s ranch in Martin Acres. Each was framed to a different standard, and each loses heat differently.
What ties them together is wind. Sitting right against the Flatirons, Boulder funnels some of the strongest downslope and chinook winds in the country — gusts that regularly top 80, even 100 mph. Wind doesn’t just make a house feel drafty; it drives cold air through every unsealed gap, stripping heat far faster than a still night. In Boulder, air sealing matters as much as R-value.
Colorado sits in IECC Climate Zone 5B, which calls for R-49 to R-60 in the attic — and Boulder’s own energy standards push further still. Many older homes we inspect measure R-19 or less. Grizzly handles every service on this page for homeowners across 80301 through 80305.
R-49+
The attic standard Boulder's climate calls for
TRUSTED PRODUCTS & PARTNERS
The Brands Behind Every Grizzly Install
We don’t install mystery material. Every Boulder project uses products from the industry’s most trusted manufacturers.
ALL INSULATION SERVICES
All Boulder Insulation Services, Grizzly
Click any service below for the dedicated Boulder page with full details, process, and neighborhood context:
Blown-in and batt upgrades to R-49–R-60 — tuned to Boulder’s wind, cold, and century-spanning housing. Most attics done in a day.
Closed-cell air-barrier foam for rim joists, vaulted rooflines, and the wind-exposed assemblies that lose the most in a Boulder winter.
Sealing the ceiling plane against Boulder’s ferocious downslope wind — before insulation goes in, because here the wind finds every gap.
HEPA-filtered removal of old, settled, or rodent-soiled material — clean deck, healthier air, disposal handled, ready for a proper reset.
Moisture-smart crawl space insulation and encapsulation for Boulder’s older cellars and creek-corridor foundations.
EPA-registered TAP® borate insulation adds thermal performance and rodent deterrence in one install — built for open-space-adjacent Boulder homes.
Spray foam and fiberglass systems for Pearl Street retail, CU-area multifamily, and Gunbarrel flex and tech space — off-hours, on schedule.
Not Sure What You Need?
Free home assessment across Boulder. We measure what your home has today and tell you exactly what it needs — no pressure.
WHY LOCAL EXPERTISE MATTERS
Boulder's Insulation Challenges
Three local realities shape how we quote, prep, and install every Boulder job — from extreme wind to a 140-year span of housing.
140 Years of Housing, One Windy Climate
Boulder’s homes span 140 years, and each era hides a different weakness. Mapleton Hill and Whittier Victorians have balloon framing and empty wall cavities; University Hill rentals were rarely upgraded; Table Mesa and Martin Acres mid-centuries carry thin, settled fiberglass. Each needs its own fix — dense-pack, top-off, or a full removal and reset.
The Windiest City on the Front Range
Boulder’s spot at the foot of the Flatirons makes it one of the windiest places in the country. Chinook and downslope gusts routinely exceed 80 mph, pressurizing the building envelope and forcing cold air through gaps around can lights, top plates, and chimney chases. Insulation alone can’t stop wind-driven infiltration — which is why we pair every attic upgrade with targeted air sealing.
Open Space = Rodent Pressure
Boulder’s open space is legendary — and it puts homes right up against prime rodent and wildlife habitat. As nights cool, mice move from the foothills and Boulder Creek corridors into warm attics. Nesting contaminates insulation and destroys R-value. We handle removal, exclusion, and borate-treated pest-control insulation in-house.
150+
Projects Completed
10 mi
From Our Shop to Boulder
TAP®
Pest-Control Insulation Partner
EPA
Registered Borate Products
WHERE WE WORK
Boulder Neighborhoods We Serve
Grizzly serves every Boulder neighborhood and ZIP code (80301–80305). Here’s how we typically approach insulation across the area:
ZIP codes covered: 80002 80003 80004 80005 80007
OUR PROCESS
How Grizzly Insulation Works in Boulder
Every Boulder project follows the same transparent path, from first call to final walkthrough, with financing made simple.
Free Home Assessment
We visit your Boulder home, measure existing insulation depth, map the wind-driven air leaks, and check for moisture or rodents. No charge, no obligation.
Clear, Itemized Quote
A detailed written quote with every line item priced and explained in plain English. No mystery numbers, no pressure.
Pick Your Plan
Pay up front or choose a monthly payment option that fits your budget. Apply in seconds, decisions are fast.
Professional Installation
Our crew air-seals, cleans, and insulates — most Boulder attics in 1–2 days — and hauls away every scrap of debris.
SAVE ON YOUR PROJECT
Boulder Insulation Rebates & Incentives
Most Boulder homes are served by Xcel Energy, and qualifying insulation and air-sealing upgrades earn meaningful rebates — on top of the county and city efficiency programs Boulder is known for. We handle the paperwork so your project qualifies.
Xcel Energy Rebates
Rebates available for qualifying insulation and air-sealing upgrades in Xcel service territory, which covers Boulder.
Federal 25C Tax Credit
30% of qualifying insulation project costs, up to $1,200 per year, under the Inflation Reduction Act.
Flexible Financing
Monthly payment plans so you can fix the attic now and pay over time, apply in seconds by text or link.
REVIEWS
What Homeowners Say About Grizzly
★ ★ ★ ★ ★
We kept hearing scratching in the attic every October, and the upstairs bedrooms never held heat. Grizzly’s crew vacuumed out sixty years of filthy insulation, sealed the entry gaps, and blew in the pest-control insulation, all in one day. Two winters later: no mice, warmer bedrooms, and our January Xcel bill dropped noticeably.
S
Sarah M.
Homeowner · Mapleton Hill Boulder · Removal + Pest-Control Insulation
★ ★ ★ ★ ★
“Our old Victorian near Mapleton Hill leaked heat through every wall when the wind came off the Flatirons. Grizzly dense-packed the cavities, air-sealed the attic, and brought it to R-49. Warm and quiet now — even in an 80 mph gust.”
D
David R.
Homeowner · Martin Acres, Boulder · Air Sealing + Attic Insulation
INSULATION ARVADA
Frequently Asked Questions
Common questions about insulation in Boulder, answered straight.
Boulder is in Climate Zone 5B, where attics should carry R-49 to R-60 — roughly 16–20 inches of blown-in insulation — and the city’s energy goals push even higher. Many older Mapleton Hill and University Hill homes measure R-19 or less. A free assessment shows exactly where you stand.
Almost always — the oldest homes see the biggest gains. For a Victorian we often dense-pack the empty wall cavities and air-seal first, then top the attic to R-49+. Degraded or rodent-soiled material comes out before new goes in.
Yes, in-house. Boulder’s open space and creek corridors put homes right against wildlife habitat. We remove soiled insulation with HEPA vacuums, seal the entry points, and install borate insulation that resists nesting.
They solve different problems. Blown-in cellulose is the cost-effective choice for open attic floors where R-49+ is the target. Spray foam delivers the highest R-value per inch and doubles as an air barrier, ideal for rim joists, crawl spaces, and garages. Many Boulder projects combine both.
Often, yes. Boulder is in Xcel Energy territory, and qualifying insulation and air-sealing work can earn utility rebates, plus the federal 25C tax credit covers 30% of qualifying costs up to $1,200/year. Programs change, so we confirm current eligibility during your free estimate and help with documentation.
Most single-family projects finish in 1–2 days. An attic top-off with air sealing on a typical Boulder ranch is often a single day. Whole-home projects touching the crawl space and rim joists may run two full days. You get a clear timeline with your quote, and we stick to it.
All of them, Mapleton Hill to Gunbarrel, ZIP codes 80002, 80003, 80004, 80005, and 80007. Our crew is based in Commerce City, about 20 minutes away via I-76, and we offer free estimates across the entire city and Jefferson County.
EVERY COMMUNITY WE SERVE
Insulation Services Across the Front Range
Grizzly serves the entire Denver metro from our Commerce City base. Click your city for local details:
GET AN ESTIMATE
Schedule Your Free Boulder Home Insulation Assessment → No Pressure, Written Quote
We measure your current insulation, identify your biggest energy losses, and give you a clear, honest recommendation — warmer rooms, lower bills, and no uninvited critters in the walls.
- (303) 854-6221 · Mon–Sat 8 AM–5 PM · Sun by appointment
- info@grizzlyinsulationco.com, we reply fast, usually same day
- 7140 Ivy St Unit B, Commerce City, CO 80022, 10 miles from Boulder
Insured & Certified · 100% Guarantee · Locally Owned & Operated
Serving Boulder & Boulder County
7140 Ivy St Unit B, Commerce City, CO 80022 — fast dispatch across Boulder & Boulder County.