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Heat transfer through cement Answered

I have a garage on top of garage because my land is on a hill. The lower garage is all concrete all the way around including the ceiling. The floor in the upper garage is the cement from the roof of the lower garage. I want to heat the upper garage, but I know the floor will always be really cold because it is cement and the lower garage is not heated. The lower garage does stay quite a bit warmer than outside temps.

My question is this, If I heat the lower shop, will the floor in the upper garage and the upper garage that is insulated be warm as well? Or am I better off just heating the upper shop and having a cold floor? I spend a lot of time in the garage and would like it comfortable when I am in there.





6 weeks ago

I know from experience that oncrete stacks like yours can be a true pain.
Having said that:
Adding a vapour barrier, insulating underlay and then a floor covering like you would use in any normal house work quite well to prevent cold feet.
And if there is no major draft problems even without an insulated floor, just heating the space will make a huge difference.
You can also get so called freezer panels.
Polystyrene boards with aluminum foil on one or both sides.
Even the thin 10mm sheets prove a great heat barrier on the walls.


6 weeks ago

That is an interesting question. I'm guessing that the upper part is wood frame construction that could be insulated if you have access to the studs. There are companies that can insulate sealed walls with blown-in insulation. They cut a small hole and then patch it when they're done. Even if you don't want to insulate, it would heat up fairly quickly if your heater is big enough. I would think you would probably want to heat the part that you spend the most time in. A cold floor isn't really a problem if you're wearing shoes. Heat from the lower part would take a long time to warm the ceiling. Concrete has a lot of thermal mass.