Insulation Contractors in Portland, OR

Much of the work insulation contractors in Portland take on starts with a house that was never insulated to begin with. The city was incorporated in 1851, and whole neighborhoods were built long before anyone filled walls with insulation. In Irvington, platted in 1887, the historic district's buildings date from 1891 to 1948. Laurelhurst grew from farmland the Laurelhurst Company bought in 1909 and platted as a 144-acre residential development. Homes like these can have empty wall cavities, a shallow layer of old material in the attic and nothing under the floor.

Walls first, sometimes

In a newer suburb the attic is almost always the first project. In an older Portland house, the walls may be the bigger gap. Dense-pack insulation can be blown into closed wall cavities through small holes, from inside or outside, that are plugged and patched afterward. Before we drill, we check what is in the walls: fire blocking, plaster and lath, and especially any older wiring. Some older wiring should be evaluated by an electrician before walls around it are filled, and we will tell you if we see something that needs that step.

Attics and half-story rooms

Many older Portland homes have finished upper floors tucked under the roof, with knee walls, sloped ceilings and small attic pockets on either side. These are hard to heat and easy to overheat. Air sealing the floor of those side attics, insulating the knee walls properly and dealing with the sloped sections, often with spray foam or dense-pack, tends to make a bigger difference than adding depth to the main attic alone.

Climate notes

Portland gets about 157 days a year with measurable precipitation, with December and November the wettest months at both the airport and downtown stations. The airport averages about 36.9 inches a year and downtown about 44.1. Freezing temperatures occur on about 32 nights a year, and snowfall averages about 4.3 inches, with suburbs and hills seeing snow more often than downtown. The West Hills run through northwest and southwest Portland, and homes up there catch more wind and cold than those near the river. All of that points to a steady heating load where air leaks and thin insulation cost you every month of the rainy season.

Basements and crawl spaces

Portland has both: older homes with full or partial basements, and plenty of houses over crawl spaces. For crawl spaces we check moisture and the ground cover before insulating the floor. For basements, rim joists are often the leakiest spot in the house and a good fit for spray foam.

Historic districts

Irvington was added to the National Register of Historic Places in 2010 and Laurelhurst in 2019. Most insulation work happens inside walls, attics and crawl spaces, but if a project would change the exterior, such as drilling and plugging siding to insulate walls, check with the city about any review that might apply. Drilling from the interior is an option when you want to leave original siding untouched.

What we offer in Portland

• Dense-pack wall insulation in older homes
• Attic air sealing and insulation, including knee walls and side attics
• Blown-in cellulose or fiberglass
• Spray foam for rim joists and sloped ceilings
• Crawl space insulation with moisture checks
• Removal of old, damaged or rodent-soiled insulation

Book an inspection

Call (971) 458-8258. We look at the attic, the walls where possible and the space under the house, then give you a written quote that lays out the order of work and the materials.

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