Attic insulation cost in Portland, OR

How much does attic insulation cost in Portland?

Attic insulation in Portland typically costs $3,400 for the example home, with a range of $2,650 to $4,550. The job is blown cellulose in an open attic, brought up toward a planning target of R-60 for climate zone 4C. It is not closed-cell foam on the roofline, not wall insulation, and not a kneewall that has to be built before anyone can blow anything. The target is the one this site uses so cities can be compared. Confirm the energy code that actually applies before you treat R-60 as a legal minimum.

Why the Portland zone changes the price

Zone 4C is why the target is R-60 and not the same number as a Gulf city or a northern city. A hotter-or-milder zone uses less material in this model. A colder zone uses more. Portland has about 4,400 heating degree days and 320 cooling degree days. The national starting point for this house, before labor, is $3,110. Local labor at 1.16 adds about $290 versus a crew priced at 1.00. About 55 percent of the price is labor. The bags of cellulose are the rest, and they do not change much by city.

What the example attic is, and what yours might not be

The example home was built around 1965 and has about 1,550 square feet of floor, which this page treats as the attic area. bungalows and newer infill on small lots, wet winters, occasional heat spikes An open, walkable attic with a hatch is the typical price of $3,400. The low price, $2,650, is that attic when the hatch is easy and there is almost no old insulation to move. The high price, $4,550, is the same cellulose when the hatch is a closet ceiling, the baffles at the eaves take time, or a small amount of old material has to be raked. Knob-and-tube wiring, a wet attic, vermiculite, or a full removal before the new blow can sit above the high number. Those are different jobs. Portland labor runs above national, and the normal climate is mild and wet. Crawlspaces, oil tanks in older houses, and small lots with no condenser clearance are the local constraints. A heat dome week is not a design day this model will pretend is normal, but it is why people add one cooling zone. Permits on equipment changes are real.

What insulation does not do to the other prices

A better attic does not change the furnace sticker on the furnace page, and it does not change the roof price. It can change the yearly bill, which is why the heating page exists separately. Do not let a contractor add “you’ll save the insulation back on the furnace” into one number with no yearly bill attached. At 14.2¢ per kilowatt-hour the cooling hours matter too. PGE and Pacific Power cover the metro. Rates are moderate. The heat spike years are not the degree-day normal. This page does not promise a payback.

If you rent in Portland

Blowing an attic is an owner’s project. A renter can use the range to read a proposal for the building, not to hire an insulation crew. An owner of a different size house should set square footage in the calculator. A 900 square foot bungalow and a 2,200 square foot house are not the same number of bags. Reviewed 2026-09-01. Planning model: IECC climate zone, degree-day normals, a metro labor factor, and a residential rate used only for operating-cost context. Installed costs start from published national ranges and scale the labor share. Rents are planning medians, not listings. Reviewed 2026-09-01.

Before you accept an insulation quote in Portland, ask what R-value is already there, what R-value they will leave, and whether air sealing at the hatch and the wire holes is included. The typical price of $3,400 assumes an open attic and a top-up toward R-60, at labor 1.16. If they are foaming the roof deck, stop using this table.