Filling the Gaps

How well insulated is your home?

We thought ours was good enough—after all, we’d clambered around in the attic laying out recycled denim insulation a few years back and to no avail. We still experienced ice dams on the roof during the winter, plus the faint draft in our already chilly kitchen. And, let’s not talk about the heating bills…

My sister, who had her 50-year-old house professionally insulated last summer--who’s been bragging about her miniscule gas bills all winter--recommended the company she used, a Chicago-based company called Green Attic Insulation.

I had an estimate done, then signed on for the work. The two-man, Green Attic team arrived in a truck stacked with hundreds of bags full of cellulose insulating material. 

The cellulose insulating material is 100 percent recycled fiber. Essentially it’s shredded newspapers treated with chemicals that make it flame and mold resistant and it's unfriendly to pests. It also adds sound-proofing as a benefit and handles humidity well.

Best of all, cellulose is non-toxic and non-allergenic, which in contrast to fiberglass a material that includes formaldehyde-based glues that continue to give off gas formaldehyde after installation.

16-Inches of Deep & Fluffy

 The Green Attic team was able to insulate our main attic to an R-49 value, which works out to a 16-inch layer of insulation. (R-49 is now required by the Illinois building code for new construction in the northern part of the state. The EPA Energy Star web site also recommends up to R-49 levels of insulation.)

“If you leave gaps in the insulation, the warm air leaving your house will simply flow around the edges on its way out,” said Andrei Turea, co-owner of Green Attic Insulation. along with his partner Dima Nicolaescu.

That made sense. Think of a bowl versus a colander: An overturned bowl will tend to keep most of the heat contained beneath it. But a colander, even if you place barrier strips over most of its surface, will let air escape from any gaps you missed. And, we had missed a lot in our attic.

The men used long tubes and a powerful machine, housed in the truck, to blow the insulation edge-to-edge within the space. Within about four hours, some 70 bags of cellulose had been applied across our attic floor, including the impossible to access space under our home’s flat-roof section. (Here’s a link to  more photos of insulation done properly.) 

The Saga Continues

As it turns out, it’s going to take at last one more visit by the Green Attic team to fully insulate our home’s interior. But the next step will be below instead of above.

The two-man team investigated our crawl space and pointed to the lack of insulation between the floor joists and along the outside walls.

“That’s what’s contributing to the cool temperatures in your house,” Turea told us. “Cold air from the crawlspace chills the floors and in turn the air above.”

Adding insulation between the floor joists will have one other benefit: it will help retain heat in the pipe carrying hot water to the kitchen. 

Cost Considerations

Energy Star estimates that a homeowner can realize savings of up to 20 percent on heating and cooling costs (or up to 10 percent on the total annual energy bill), by proper sealing and insulating. If that holds true, we expect our insulation saga to give us a return on investment of about three to five years.