Q: I’m building an addition onto my house and I’m wondering what my options are for green insulation. Could you help me out?

A: First things first. Just having insulation in your house at all is considered green, so kudos. Insulation is like clothing for your house — whether it’s hot or cold outside, raining or snowing, it helps keep your house at a constant temperature. Picture this scenario: You’re stuck in the desert (don’t ask me how you got there, this is your scenario), you’re parched, sweating bullets, and you feel like stripping all your clothes from your body. Right move? Bear Grylls would tell you otherwise, my friend. You’re actually supposed to wear long sleeves and long pants to keep your body cool. Same goes for your home. If you don’t insulate your house properly, it’ll end up frying in the summer and freezing in the winter, causing your heating and air conditioning system to kick into serious overdrive. Insulation also keeps out moisture, which can prevent mold and can even help keep out noise, a plus if you live on a busy street or near a highway.

Though I may not be a construction guru, I’m married to one. My hubby records every episode of This Old House and I sometimes find myself watching them at 3 in the morning when I can’t sleep (there’s something about home renovation shows that I find oddly comforting). I saw an episode the other night about foam insulation, which looks really fun to play in and happens to be one of the greenest options out there today, even though in the past, it’s gotten a pretty bad rap.

In the '70s, lots of people used UFFI (urea formaldehyde foam insulation) to insulate their homes, but experts soon realized that it caused formaldehyde to leak into the air. For those of you keeping score, formaldehyde is a dangerous chemical that has been linked to cancer — no fun.

These days, much of foam insulation is made of Icynene, which is water-blown and therefore not nearly as harmful as the foam of yesteryear. There’s even a company in Canada that makes foam insulation out of plastic bottles!

Though a bit pricier than other types of insulation, most people believe that foam is the best insulation there is to keep outside air where it belongs: outside. With foam, your home is totally sealed, like a present under the tree the night before Christmas.

Another green option for insulation? Recycled denim. No silly, this doesn’t mean breaking out your bellbottoms for a little Saturday night dance-off action. Shredded jeans can actually be used effectively to insulate a house without any harmful chemicals, just good old-fashioned cotton. Don’t ask me where they came up with the idea —  “I have a lot of these old jeans … and man, it is cold in here … hey, wait a minute …”) And in case you’re thinking about donating your old pairs, you should know that most recycled denim insulation is made using scraps from manufacturers and not old jeans they pulled out of the garbage.

Finally, if you consider yourself dark green, you might want to check out HempFlax insulation or straw-bale construction.

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