Typical Seattle Insulation Crew
Attic Insulation &
Air Sealing in
Seattle & King County
Licensed Washington general contractor serving Seattle, Redmond, Bellevue, Sammamish, Mercer Island, Kirkland, and Greater King County. HM-PRO provides attic insulation, air sealing, blower door testing, thermal imaging, ventilation improvements, ductwork corrections, and documented home energy performance upgrades.
At HM-PRO we diagnose your attic with professional blower door testing
and thermal imaging, fix the real issues - air leaks, ductwork,
ventilation, bath fans - then insulate properly and re-test to prove the
result.
Book Attic Assessment Professional Attic Insulation for Seattle Area Homes
HM-PRO is a licensed Washington State general contractor specializing in attic insulation, air sealing, and home energy performance for homeowners across Seattle, King County, and Snohomish County. We serve Redmond, Bellevue, Sammamish, Kirkland, Mercer Island, Woodinville, Issaquah, Bothell, Monroe, Snohomish, Mill Creek, and nearby communities.
Unlike commodity insulation contractors who simply blow new cellulose over existing problems, we measure first, fix the actual issues, and verify the result. Every project starts with blower door testing and thermal imaging to find where your home is losing energy. Then we seal penetrations, correct ductwork and ventilation issues, install proper baffles, and insulate to the target R-value.
Unlike commodity insulation contractors who simply blow new cellulose over existing problems, we measure first, fix the actual issues, and verify the result. Every project starts with blower door testing and thermal imaging to find where your home is losing energy. Then we seal penetrations, correct ductwork and ventilation issues, install proper baffles, and insulate to the target R-value.
Licensed WA General Contractor
Washington contractor license #HMPROL*792CH.
Blower Door
Tested
Tested
We measure air leakage before and after the work instead of guessing.
Thermal Imaging Diagnostics
Infrared scanning helps locate hidden attic air leaks, cold spots, and insulation gaps.
Five-Star Local Reputation
315+ five-star reviews across Google and Thumbtack. Confirm current count before publishing.
WE DON'T GUESS. WE TEST
Insulation Alone Does Not Stop Air Leaks
Many Seattle homes lose heat through small openings around recessed lights, attic hatches, top plates, plumbing penetrations, bath fans, and disconnected ductwork. If those leaks are not sealed first, new insulation can still underperform because warm indoor air moves through it and escapes into the attic.
That is why HM-PRO treats the attic as part of the whole house. We look at air movement, moisture risk, ventilation, ductwork, and insulation depth before recommending the scope of work.
That is why HM-PRO treats the attic as part of the whole house. We look at air movement, moisture risk, ventilation, ductwork, and insulation depth before recommending the scope of work.
What Is Included in Every Attic Project
Our standard attic package is built around measurement, correction, insulation, and verification. The goal is not just more R-value. The goal is a tighter, better-performing attic with documented results.
-
Blower Door & Thermal Test
Pre-work diagnostic testing measures air leakage and helps identify hidden leak points. -
Old Insulation Removal
Settled, damaged, or contaminated insulation is removed before new work begins when required by the project scope. -
Air Sealing
Gaps and penetrations are sealed with appropriate sealants and fire-rated materials around key leakage points. -
Recessed Light Covers
IC-rated covers help separate fixtures from insulation and reduce leakage paths. -
Soffit Baffles
Baffles protect soffit-to-ridge airflow, which is important for Pacific Northwest moisture control. -
Ductwork Corrections
Damaged or disconnected attic ducting can be replaced or corrected so conditioned air reaches the room, not the attic. -
Blown-In Insulation
New attic insulation is installed after sealing work, targeting proper performance for the home. -
Post-Work Verification
A follow-up blower door test documents the improvement instead of asking you to trust a guess.
Diagnostic Process
We Measure Before We Work. And Again After.
Blower Door Air Leakage Test
A calibrated blower door test measures total air leakage before work begins.
Thermal Imaging Scan
With the home under pressure, infrared imaging helps reveal air leak points that are not visible during a normal attic inspection.
Hands-On Attic Restoration
We seal penetrations, correct ventilation and duct issues, install baffles, and add insulation according to the agreed scope.
Verification Test
After the work is complete, we re-test and provide documented before/after results.
Case Study
Real Project
Woodinville, WA
The Problem
The Problem
Drafty rooms. High bills. New-ish house.
Despite being only 18 years old, the home tested at 5.32 ACH50 — well above WA energy code's 4.0 target. Cold spots in the bonus room. HVAC running constantly. The owner suspected insulation. We suspected something else.
The Diagnosis
The Diagnosis
Thermal imaging revealed the leak map.
With the Retrotec blower door depressurizing the home, our Fluke scan documented these primary leak sources:
Recessed light fixtures | +13.3°F |
Disconnected duct in attic | +11.5°F |
Attic hatch perimeter | +9.1°F |
Bath fan penetrations | +7.8°F |
Top plate transitions | +6.2°F |
The Result
The Result
Documented. Honest. Verifiable.
Air leakage reduced by 827 CFM50 — equivalent to closing a 10×10 inch hole in the building envelope. Estimated annual heating savings: $400-650. Work completed in 2 days, no drywall touched.
- 5.32 ACH50 - Before
- 4.27 ACH50 - After
- 19.7% air leakage reduction
- 827 CFM50 leakage eliminated
MEASURED BEFORE. VERIFIED AFTER.
Licensed. Trained. Equipped to Test.
Most attic insulation contractors in the Seattle area hold no formal certifications beyond a basic license. The work that separates real building performance from commodity insulation requires specific training — Building Performance Institute methodology, calibrated equipment operation, and an understanding of how houses behave as systems.
Washington State General Contractor
Lic. #HMPROL*792CH, active/bonded/insured. Confirm status before publishing.
BPI Building Science Training
Building science methodology for understanding how homes perform as systems.
Retrotec Blower Door Operation
Professional equipment operation for measured air leakage testing.
Five-Star Reputation
Use current Google/Thumbtack counts only after final confirmation.
Professional Equipment
The Same Type of Tools Used in Home Performance Testing
Most insulation estimates are visual. Our assessment uses measurement instruments: blower door testing, pressure gauges, thermal imaging, and written documentation. This gives the homeowner a clearer picture of what is actually happening before money is spent on insulation.
- Blower door fan and pressure gauge - Measures leakage under controlled conditions.
- Thermal imaging camera - Helps locate temperature differences caused by air movement and missing insulation.
- Written reporting - Creates a before/after record of the work.
Why HM-PRO Costs More Than Basic Blow-In Insulation
Adding insulation without air sealing first is like wearing a wool sweater with the buttons open. R-value loses real-world performance when air moves freely through it.
HM-PRO Attic Performance
INSULATION IS ONLY PART OF THE JOB.
Attic Insulation Cost in Seattle: Standard and Premium Packages
Final pricing depends on attic size, access, contamination, ventilation, ductwork, and selected upgrades. The assessment confirms the exact scope before work starts.
Minimum project size: $7,500. Confirm current prices before publishing.
Standard Attic Performance
Typical project: $8,000 - $15,000
From $6.95 / sq ft
- Blower door + thermal scan
- Old insulation removal when included in scope
- Air sealing
- Recessed light covers
- Soffit baffles
- Ductwork corrections as scoped
- Blown-in insulation
- Post-work verification
- Written documentation
Premium Attic Performance
Typical project: $12,000 - $22,000
From $9.95 / sq ft
- Everything in Standard
- Bath fan replacement options
- Radiant barrier option
- Rodent-resistant soffit vent screens
- More detailed thermal reporting
- Priority scheduling when available
Start With a Free Phone Consultation
Have questions about attic insulation, air sealing, rebates, or project cost? Start with a short phone consultation. We will help you understand whether your home is a good fit for an attic assessment.