Does rigid slab insulation negatively affect the cooling properties of a basement?
MikefromtheMountainsofUtah
| Posted in General Questions on
Zone 5, mountains of Utah.
Adding an addition that will be built into the hillside. Radiant heat in the slab.
While lack of insulation obviously means it’s going to take more radiant heat to keep it warm in the winter, does it also decrease the cooling effect of the earth on the basement in the summer?
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Replies
It does. It also leaves the slab cool enough to result in condensation when the dew point is high enough.
Utah is dry enough that condensation might not be a problem, but you will use a LOT more energy keeping the slab warm in winter than you will reducing the load in summer.
Thanks for the quick reply and help. Sounds good and we'll stick with the plan.
Where I am, Washington, DC, basement floors are typically not insulated but the walls are. The floor contributes more to cooling in the summer than it costs in the winter.
If you're running radiant heat you have to insulate under the slab.