Insulating basement ceiling/first floor
I suspect this has been much discussed, so feel free to bump me over to a thread if one exists…
We have a relatively modern (1981), reasonably efficient gambrel in Maine. Full basement, concrete foundation, unfinished (used for storage and a workshop. Not heated, but gets residual heat from the oil boiler. Temp hovers between 50 and 70, depending upon what the boiler is doing.
The previous owner had partially insulated the ceiling of the basement with foil-faced R-19 fiberglass, foil facing into the basement. I’ve discovered that our local mouse population has made that insulation their home, so I’m tearing it all out.
Question – should I replace it? I understand there’s some controversy over this practice. I am insulating the rim joist using solid foam and filling the gaps with expanding foam.
If I should have some kind of insulation under the floor, would a foam board work as well?
Thanks,
John
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Replies
John,
The best way to insulate a basement is to insulate the walls, not the ceiling.
If I were you, I would remove all of the mouse-infested fiberglass insulation and put it in a dumpster.
Then I would insulate the basement walls. Here is a link to an article that explains the required work: How to Insulate a Basement Wall.
Thanks! I'm delighted to hear that.
John