My house has no attic insulation, so I plan to take care of that this summer. I grew up in a house that had vermiculite insulation, but somebody at the home improvement store said they don’t stock it because it doesn’t work as well as what they’re selling. He also said that it’s toxic, which I find hard to believe. Obviously, I need an objective opinion. Can you help?

Glad to. The use of vermiculite as insulation has largely fallen out of favor since it was found that a big percentage of the vermiculite sold in the US between 1919 and 1990 came from an asbestos contaminated mine in Libby, Montana. This is also why vermiculite that’s already in a house should be left alone or addressed by a trained professional. Today, vermiculite can be found at some building supply locations as well as some local garden centers.

As for its effectiveness, vermiculite has an R-value per inch of about R-2, making it one of the least effective insulation choices for an open attic. (R value shows you how well a material prevents the escape of heat. The higher the value, the better the material insulates.) Other options include loose fill cellulose insulation which is about R-3.5 per inch. Be certain to seal air leaks first and to see that the insulation is properly and thoroughly installed. To get the most energy savings from this investment, it’s best to use a professional. You can find a list of Home Performance with ENERGY STAR® contractors in Vermont at www.efficiencyvermont. com/homeperformance. Efficiency Vermont offers financial incentives to homeowners for energy-saving improvements completed by these contractors.

Bob for The Home Team

We fenced in our yard so that the dogs can run free out there. Now we’re thinking about putting in a pet door, but we’re concerned that it will let in cold air next winter. But on the other hand, the little door would let in less air than opening the “people” door for the dogs. Are pet doors considered energy savers or wasters?

I don’t have figures for you about the exact amount of heating energy that a pet door wastes compared to a full-sized door. However, a big door that’s opened a few times per day will typically let in less outdoor air (and let out less indoor air) than will a pet door that constantly leaks air.

Some pet doors leak less than others, though. The pet doors that have a double-layer rigid door instead of a flap are likely to leak least. Pet doors with an inner and outer flap, especially if they have a magnetic seal, are also an improvement over the leakiest pet doors. If you want to conduct an experiment next winter, visit friends with different kinds of pet doors. You’ll be able to feel how much cold air is coming in and get a general sense of what you’d be comfortable installing in your home.

Kathleen for The Home Team