Freeze Thaw in Unheated Attached Garage
Hey All,
Currently working through a new build in CZ6, Idaho. Framing is just about to be completed and the roof is getting put on, windows and doors set by end of the month. It’s definitely winter. Snowing a little each week, lows at night in the teens, etc.
I understand builds happen through winter all the time, but just wanting to best set the home up for success. From what I’ve read on this site from similar questions, one of the best things to do is to run temp. heat to keep the foundation from freezing and shifting. That all makes sense and we can do this until HVAC has installed actual heat which will then run constantly.
However, we have a drive under, attached garage in half of the basement. In thinking through this space (both short term and long term), since the garage space won’t be heated normally, will its foundation be at risk of shifting in the freezing temps? Or will the adjacent warm spaces keep it at a bare minimum temperature where it’s not cause for concern. Obviously lots of unheated, uninsulated, attached garages out there in the world — I just hadn’t really thought about this situation until now and curious to hear others thoughts.
Additionally, if anyone has other advice on keeping the build in good shape over the winter, I’d love to hear.
As always — thanks and appreciate the input.
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Replies
It depends on whether you have a fpsf
Sean,
As long as the garage foundation either goes down to the frost depth for your climate, or is insulated as a FPSF, it will be fine.
Thanks Malcom -- The foundation walls go down to frost depth for our climate
Sean,
It's crawlspaces and basements that can make foundations built down to frost vulnerable by creating a path for cold air to avoid the insulation the earth around the structure provides on the outside.
Garages and houses with slabs on grade don't have that problem, but the slabs themselves can heave if there is damp fill below. That's rare though.