Do you realize how much you could save if you insulated your house better?
The Hive
Collective wisdom.
March 9 2010 11:20 AM

If These Walls Could Talk

They would say, "Insulate us!" The case for better—much better—insulation.

Home scan. Click image to expand.
Home scan using a thermal camera

Throughout this process of trying to make my home more energy efficient, I've been treating my house as a patient. The home energy assessment conducted by the Moldovan brothers was like triage. They conducted some tests, tightened a few things here and there, and made fixes that should improve the health of my energy bills. But they also noted that there was more to be done. And so I called in specialists who could give the house the equivalent of a CAT scan.

The house call was made by Joe Novella and Chris Jobson of Green Star Energy Solutions, who are experts on building performance. My house bombed.


When energy assessment pros set up the blower test, you can feel air—and money—literally slipping through the cracks. But there are so many other places in a house (especially in a house like mine that is much wider than it is high) that represent leakage opportunities: corners, joints, interior and exterior walls, foundations, roofs, floors, vents for fans and clothes dryers. Most of these problem areas are invisible to the naked eye. I learned that it is possible to visualize the air—and money—rushing in and out of the house. Novella pulled out a fancy Fluke thermal camera (sticker price: about $4,000). And we went hunting for cold and heat. Novello aimed it at the walls. It was shocking: deep-blue, money-sucking pools in cracks, in corners, in walls and ceilings where insulation had fallen down or been pushed aside, strange cavities that had been created by alterations of the house's structure over the years. Insulation, it turns out, can be easily displaced by people poking in wires, vents, light installations, and all kinds of other things. Would it surprise you to learn that the electrician who installed your recessed lights just shoved the insulation aside and didn't put it back when he was done? It surprised me.

Novella, who agrees wholeheartedly with President Obama that insulation is sexy, patiently explained the science behind air flow, the difference between fiberglass and spray foam insulation, and how to convert increased "R-values" into cash savings. I nodded and pretended to understand. Jobson took notes, drew sketches, and occasionally made pained expressions when looking at the workmanship around the house. Some insulation had been installed upside down. A layer of insulation in the ceiling of our unfinished basement has a plastic sheet under it, which, they noted, would trap vapor and foment the growth of mold. At times it felt like I was filming a pilot for a reality show: America's Worst-Insulated Homes. "Chris, get a load of this," Novello called out, as I wriggled into our attic. A roll of insulation was peeled back to reveal a gaping void in the woodwork.

The upshot: I probably need more (and in some instances, better) insulation. And I'll be happy and eager to look at the spreadsheets that indicate how much I could theoretically save on heating and cooling by making particular improvements in my thermal envelope.

But this isn't simple. Insulation is more expensive and more intrusive than things like smart meters, programmable thermostats, or compact fluorescents. Improving your insulation could involve cutting holes in walls and ceilings, ripping some stuff out, and blowing or rolling other stuff in. The good news is that, if you live in Connecticut, your fellow electricity ratepayers will pay for a lot of it. Connecticut's Energy Efficiency Fund is running a special in which it'll rebate up to 50 percent of the cost of new insulation, and there's a 30 percent federal tax credit. Unless I'm misunderstanding the way it works, you spend $2,000 on new insulation and could get a rebate of up to $1,000 and a tax credit of $667 (depending on your tax bracket), meaning the net cost to you at the end of the year is $334. How long would this investment in better insulation take to pay off in lower heating and cooling costs? One year? Three years? Novella said that most insulation jobs can essentially finance themselves out of reduced energy expenditures over a three-to-five-year period.

How has insulation paid off for you? Are your thermal images as ugly as mine? Rolled out or blown in? Share your experiences in the comments section below.

Slate is seeking the best ideas for helping people use less energy at home and save money. You can submit your proposal here, see the 10 most-popular reader proposals, and scan all the proposals submitted by readers so far. At the end of March, when we choose the top ideas, I'll commit to making changes in my use of energy. And over the course of the next year, I'll provide progress reports on whether my efficient life is living up to its promise.

