Basement Floor/Ceiling insulation?
truthbox
| Posted in Energy Efficiency and Durability on
Hi,
Like all good GBA readers I know that basement walls should be insulated. However, in many existing homes I see insulation installed in the floor/ceiling assembly between the basement and the conditioned space above. Assuming for the sake of conversation that the basement walls aren’t insulated (or can’t be insulated due to budget constraints) and the basement is semi-conditioned space with mechanical equipment does this insulation in the floor/ceiling assembly serve any purpose? That is, is there any reason to maintain this insulation?
Thanks,
Rob
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Replies
Rob,
Strictly speaking, the answer is "it depends." If the heating appliances are oversized, and the basement ductwork is leaky, it's theoretically possible for a basement to be hotter than the floor upstairs in the middle of winter. Under those circumstances, you wouldn't want any insulation in the basement ceiling.
More typically, in winter the basement is cooler than the floor upstairs. If the living room thermostat is set at 72 degrees F, it might be 60 or 65 degrees F in the basement. Under those circumstances, the insulation in the basement ceiling helps somewhat -- by lessening heat flow from the upstairs conditioned space to the basement below.