Does adding basement insulation pay for itself?
davidmateroarchitecture
| Posted in Energy Efficiency and Durability on
Hi,
Does anyone have data on whether adding spray foam insulation and sealing the sills to a full concrete basement will pay for itself in reduced fuel costs?
Thanks,
Josh
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Replies
There's no set answer. How much it saves depends on where you live, what you use for heat and what it looks like currently. Whether it pays for itself depends on how much it's going to cost, what you project the inflation in fuel costs to be in the future, and your cost of funds.
In addition, you either have to live in the home for a long time OR be assured that a future buyer will value your insulation improvements at some substantial value. Home improvement projects usually never pay back at resale, even the glossy ones.
Unless you have an exceedingly air-leaky basement, you're probably not likely to pay off a full insulating project in a short period of time. That doesn't mean that's always the case though -- and there are other reasons to do the work. You can cut down on drafts, and make your home more comfortable, with air sealing and insulating projects -- it's not only about cost savings.
My own recommendation is typically to do the air sealing and insulating in rim joist areas as a minimum, since that tends to be where you get the most benefit for the least total investment. If you want to go further you can, but if you have a poured foundation, I would use rigid foam board and not spray foam on the walls.
Bill