Attic air sealing in Bellingham WA - a sealed attic that keeps your heat downstairs
Drafty rooms, a hot upstairs or a power bill that keeps climbing? We check your attic first, then seal the gaps your heat escapes through.
- The owner comes out I look at the attic myself and show you what's there.
- Checks before sealing We look the whole attic over before anything gets sealed.
- Vents left clear Soffit and ridge vents stay open so the attic can breathe.
- A plan in order Your written plan says what happens first and why.
- Licensed and fully insured.
- Free on-site estimates.
- Expect a reply within 1 business day.
How can you tell your attic needs air sealing?
A leaky attic usually shows up in the rooms below before anyone looks up there, and catching it early keeps a small sealing job from turning into a moisture problem.
Drafts around ceiling lights
You feel cool air near the can lights or the attic hatch. That usually means open gaps into the attic, and you keep paying to heat air that leaks away.
Upstairs too hot or too cold
The bedrooms upstairs run hotter or colder than the rest of the house. Air moving through attic gaps is often the cause, and more insulation alone won't fix it.
A power bill that keeps climbing
Your bill creeps up even though nothing about how you live has changed. Leaks into the attic are a common reason, and that cost comes back every month they stay open.
Dark streaks in the insulation
Gray or black streaks on old insulation show where air has been pushing through and leaving dust behind. Those spots mark gaps that need sealing before anything new goes on top.
Damp wood in the attic
The rafters or roof boards look damp or stained. Warm, moist house air leaking up can do that, and left alone it can lead to mold and rot.
Insulation that never seems enough
You've added insulation and the house still feels drafty. Insulation slows heat but doesn't stop moving air, so unsealed gaps keep working against what you paid for.
What attic air sealing involves
Attic air sealing in Bellingham, WA means closing the gaps where warm house air slips up into your attic, and at Thermal Bellingham Insulation Company we do it in order. I look the attic over before anything is sealed, because closing gaps over a problem only hides it. Then our installers pull back old insulation where they need to reach, and they seal the gaps around lights, pipes, wires and chimneys. We leave the soffit and ridge vents clear, the openings along the eaves and the roof peak, because the attic needs them to breathe. The price and the schedule mostly turn on how many gaps there are, how much insulation has to be moved to get at them and whether the check turns up something to fix first, and your written plan lays that out step by step.
Sealing is usually the first half of a bigger fix. Once the gaps are closed, we can add retrofit insulation to build up what an older house already has without starting over. Spray foam insulation seals and insulates at the same time, but it costs more, so I usually recommend sealing the gaps and topping up with blown-in insulation, loose fill blown through a hose, unless your ductwork runs through the attic. In that case foam is often worth the extra.
What happens after you call about attic air sealing?
You talk with me at the start and the end, and our installers do the sealing in between, following the plan we agreed on.
Call or send a request
Call (360) 255-0276 or use the form, and I come out myself to look over the attic and show you what I'm seeing.
Read your written plan
You get a written plan that puts each step in order and says why it comes there, so you can see what has to happen first.
Our installers seal the attic
Our installers follow the plan in that order. If the check turned up something that needs fixing, that gets handled before any gap is sealed.
Walk through it together
When the work is done, I walk through it with you and point out what was sealed, so you know exactly what's in your attic now.
Why Bellingham homeowners call Thermal Bellingham Insulation Company
I look at your attic myself
I come out to see the job and build the plan with you, so the person planning it has actually seen it.
Checks first, then sealing
I spent years scheduling contracting jobs and saw what out-of-order steps cost, so your plan starts with the checks.
Working in Bellingham since 2023
We started here in 2023, and three years in, most calls come from owners of drafty or older houses.
A licensed, fully insured business
Our installers work in your attic for a licensed, fully insured business, so you aren't carrying the risk of the work.
Get a written plan for your attic air sealing
Send your address, whether you live there and what you know about the attic insulation. We reply within one business day to set up your free on-site estimate, and I come out myself, with no obligation to go ahead.
Attic sealing examples
Look through these examples of attic air sealing and insulation work to see what sealed gaps, clear vents and an even layer of insulation look like.
Attic air sealing questions
These are the questions people ask most about sealing an attic here. If your attic doesn't fit neatly into any of them, call and ask about your own house.
How much does attic air sealing cost in Bellingham, WA?
I give you a figure after I've seen your attic, because the cost comes down to what's up there. Lots of fixtures and pipe holes, a tight space to crawl through, a chimney to seal around or old insulation that has to come out first all add to the job. Your estimate lists each step in order, so you can see where your money goes.
What do you use to seal gaps in an attic?
Caulk goes into narrow gaps and spray foam fills wider ones, and caulk near a heat source should be rated for high temperatures. Around chimney and flue pipes, the seal should be heat resistant, such as sheet metal, to protect against fire. We pick the material by the size of the gap and how hot that spot gets.
What does an attic check look for before air sealing?
I look for live knob and tube wiring, the old wiring strung on ceramic knobs, loose vermiculite insulation, bathroom fans that vent into the attic instead of outside, and roof leaks. Any of those has to be dealt with before sealing, because closing gaps around a problem just traps it. You can ask for this check as the first step of the job.
How do I know if asbestos rules apply to my attic in Whatcom County?
The Northwest Clean Air Agency requires remodeling and demolition projects in Whatcom County to find out whether asbestos is present before work starts, and that includes a home you own and live in. At an owner-occupied, single-family home that's your main residence, that survey doesn't need a certified asbestos surveyor. Loose vermiculite counts as asbestos under the agency's rules unless sampling shows it's 1 percent asbestos or less, so if I find it up there, that question gets settled before anyone disturbs it.
What is the best order for air sealing and insulating an attic?
Safety and fresh air come first, then the attic's own condition, then sealing, then insulation. That means making sure your furnace, water heater or other fuel-burning equipment still runs safely and the house gets fresh air, then fixing things like roof leaks and keeping the attic vents working before any gaps are closed. Sealing goes in before insulating because that's where the work saves the most energy.
Do landlords need a certified asbestos contractor in Washington?
Yes, if asbestos has to be removed, owners of apartments, multifamily homes and rental units must use only a Washington state-certified asbestos abatement contractor. A homeowner working on the single-family home they own and live in is exempt from worker certification, but every other rule still applies. If you're a landlord or property manager, tell us when you get in touch so the plan accounts for it.
Cities we work in
We work across Whatcom and Skagit counties, so pick your city below. Many Bellingham addresses sit outside city limits, and we confirm which office covers yours.
Have your attic checked before it gets sealed
Our work is backed by our satisfaction guarantee, and a look now shows what to fix before you spend on new insulation.