Blown-In Insulation in Iowa City, IA

Blown-in insulation is often the most economical choice for attics with open floors and for older walls that were never filled. It is loose cellulose or fiberglass blown through a hose to fill around joists, wires and pipes. HomeGuide lists blown-in at about $1.00 to $2.80 per square foot, and Fixr at $1.65 to $3.80.

In the attic

Most attic jobs we quote in Iowa City combine air sealing with blown-in insulation. Foam seals the gaps, and loose fill adds the bulk R-value at a lower cost than foaming the whole floor. Cellulose and fiberglass both work. Cellulose is denser and resists air movement better. Fiberglass is lighter and does not absorb water. We explain the choice for your attic on the quote.

In existing walls

About 11.8% of Iowa City homes were built in 1939 or earlier, and many older houses have empty wall cavities or a few inches of material that has slumped. Dense-pack cellulose can be blown into those walls through small holes drilled from outside or inside, then patched. HomeGuide puts dense-pack at $1.60 to $4.20 per square foot. Before we drill, we check for knob-and-tube wiring, which should not be buried in insulation until an electrician has dealt with it.

Depth and settling

Loose fill settles a little over time, so we install to the settled depth the manufacturer lists for your target R-value and put depth rulers in the attic so you can check. The Department of Energy notes that the R-value of loose fill does not scale perfectly with thickness, which is why we go by the bag chart instead of a rule of thumb.

Garage ceilings and knee walls

Blown-in also works in enclosed spaces like the ceiling of an attached garage under a bonus room, as long as there is a way to contain it. Get a free estimate