Blown-In Insulation Eugene, OR

Settling Is Normal, and It Is Priced In or It Is Not

Loose-fill material compacts over time. Cellulose settles more than blown fiberglass, which is why it is installed above the target depth rather than level with it, so that the settled depth is the rated depth. A contractor who fills to the finished number on day one is selling an attic that will be under specification within a couple of seasons. It is also why an attic insulated years ago can measure well short today without anyone having done anything wrong at the time.

Air Sealing Comes First, Every Time

Blown-in material sits on the ceiling plane and does nothing to stop air passing through it. If the ceiling below is leaking at recessed lights, top plates, plumbing penetrations and the attic hatch, conditioned air moves straight through the fibres regardless of depth. Sealing those paths before the material goes down is what makes the depth meaningful. Blowing new insulation over an unsealed ceiling is the most common way money gets spent on an attic without the house changing.

Cellulose or Blown Fiberglass in a Damp Climate

Cellulose is denser, made largely from recycled paper, treated for fire resistance, and it resists air movement better. It also absorbs and holds water more readily than fiberglass, which matters in a climate this wet if there is any history of a roof leak. Blown fiberglass is lighter, handles damp conditions with less risk, and adds almost no load to a weak ceiling. The attic, the ceiling structure and the moisture history decide it.

When Blown-In Is the Wrong Answer

If ductwork or an air handler sits in the attic, material on the floor leaves that equipment in unconditioned space and foam at the roof line is usually the better spend. If the attic is partly finished or used for storage, a floor fill gets compressed and stops working. If the existing material is damp or contaminated, nothing should go on top of it until it has come out. We will say so in each case rather than quoting the easier job.