If your floors are cold in January, one bedroom is unusable in August, and the furnace runs constantly in between, the problem is usually the envelope rather than the equipment. Tell us about the house and we'll match you with an insulation contractor in Portland who measures before blowing anything in.
Air sealing before insulation, every time. Sealing the attic plane — top plates, chases, can lights, the hatch — is cheaper than insulation and does more. Then attic insulation to a proper depth, then the crawlspace floor and rim joists, then walls if you're already opening them. Anyone who wants to blow eighteen inches of cellulose over an unsealed attic is selling material, not performance.
Most Portland houses sit over a vented crawlspace with bare soil, damp air, and either no insulation or batts that fell down years ago. A ground vapour barrier, sealed and insulated rim joists, and properly supported floor insulation change how the whole house feels underfoot. It's also where rodents and moisture problems announce themselves, so the crew should report what they find down there.
Dense-packing cellulose into 1920s balloon-framed walls works, but it needs someone who understands fire blocking, the absence of a vapour retarder, and — critically — whether live knob-and-tube wiring is still in those cavities. Burying active knob-and-tube in insulation is both a code problem and a fire risk. A good contractor checks first and tells you if an electrician needs to go ahead of them.
Describe the project once and we match it with vetted local pros who actually do this work — you choose who to hire, or nobody at all.
For decades the pitch here was winter comfort. After repeated heat domes, the attic that keeps heat in during February is also the thing keeping your upstairs survivable in August. Radiant heat through an underinsulated roof plane is what makes second floors ten degrees hotter than the rest of the house.
Utility and state energy programs in Oregon routinely offer incentives for attic, floor, wall, and duct insulation, and they generally require a participating, licensed contractor plus documentation of before-and-after conditions. Doing it cash and off-book usually forfeits that money. Ask which programs a bidder is enrolled in before you sign.
In a climate this wet, insulation done without attention to ventilation and vapour causes rot rather than preventing it. Attics need intake and exhaust airflow above the insulation; crawlspaces need the ground covered; bath and kitchen fans need to terminate outside. Sealing a leaky house without addressing ventilation is how people end up with condensation on interior walls.
Attic air sealing plus blown insulation on a typical single-storey footprint commonly runs $2,000–$4,500. Crawlspace work — vapour barrier, rim joist sealing, floor insulation — frequently lands in the $2,500–$6,000 range depending on access and how much old material has to come out. Dense-packing existing walls generally prices per cavity and often totals $4,000–$10,000 on a whole house. Incentives can offset a meaningful share. A bid that quotes R-value and square feet but never mentions air sealing is not the same product as one that does.
They spent most of the first day sealing the attic before insulating. Upstairs is finally a normal temperature in both January and August.
Crawlspace had bare dirt and fallen batts. New barrier, sealed rim joists, insulated floor. The kitchen floor isn't painful in winter anymore.
I asked about drilling the walls and he talked me out of it on a 1920s plaster house, then put the budget into the attic and rim joists instead. Honest advice that cost him work.
Attic air sealing and insulation, almost always. It's the cheapest per unit of comfort, it helps in both seasons, and it's the least disruptive. Crawlspace work is a strong second if your floors are cold.
Not over or around live knob-and-tube — the wiring was designed to shed heat into open air. If those circuits are still energized, they need to be replaced or de-energized first. A reputable contractor will inspect for it and stop rather than bury it.
It can be, particularly for rim joists and for converting a crawlspace to conditioned space, but it's unforgiving of a wet substrate and it hides future moisture problems. Many local crews prefer a sealed vapour barrier plus batts or rigid board for that reason. Get both approaches priced.
Most attic and crawlspace jobs are one to two days. Whole-house dense-pack takes longer and involves drilling and patching from inside or outside. None of it requires you to move out.
It helps, and it's often required to access incentive programs. A blower-door test tells you where the leakage actually is rather than where you assume it is, and the report gives you a way to compare contractors' proposals against a common baseline.
Tell us the age of the house, the cold rooms, and the hot ones. Portland insulation contractors reply with free assessments and quotes.
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