Insulating a Concrete Foundation Wall
Hi,
I am soon to be building a garage in Wisconsin (Climate Zone 6b). The framing will sit on 4’ frost walls with a 6” slab on the inside. I will be running a radiant heat system in the entire building (37’ x 66’). I am looking for guidance as I choose how to insulate the foundation and slab most efficiently. Here is what I am thinking:
Foundation: 2” of eps on the outside of the foundation wall
Slab: 2 layers of 2” eps (4” total) under slab
I am also considering using either 1” or 2” eps on the outside of all the exterior walls. The exterior walls will be blown in fiberglass along with the attic.
My main question is weather or not I should have the foundation insulation layer on the inside or the outside of the 8” concrete foundation wall? Also is 4” of insulation overkill under the slab?
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Replies
Here are a few resources that should prove helpful:
What’s the Best Way to Insulate a Basement Slab?
How to Insulate a Basement Wall
Insulating a Raised Slab
Getting Slab-Edge Insulation Right
假设所描述的组件具有倒入霜壁的板坯的一个思想，该思想是抵靠霜壁的板坯，是加热的板坯通过传导到墙壁上的周边和下部的绝缘和脚下的土壤而失去一些热量。您可以将绝缘层放在霜壁的内侧，从脚踏到顶部，并将子板式绝缘层放置在内。在外面的位置，必须保护霜壁绝缘免受紫外线和物理（“杂草吹拂”）损坏。如果在内部，则必须保护上方的任何投影必须免受物理损坏以及热/点火原因的保护。如果是这种情况，这种保护可以由水泥板（例如，DUROCK）提供，放置在倒在板坯之前，突出1/2“在泡沫顶部上方。2×层可以放在顶部霜壁/泡沫板，带有一个dado切入2x的底部以捕获水泥板的顶部。这种安排在我自己的车库里面使用。
With a heated slab, 4" of insulation beneath it certainly is not too much, considering the huge surface area. You could estimate the loss for any thickness of the insulation, using a slab temperature somewhat above inside air temperature and an assumed ground temperature below the insulation. But there is some uncertainty in that ground temperature, and it won't be quite what deep ground temperature is. The ground will be heated to some extent by heat loss to it, and that heat gained will be passed on to the ground further down, according to the thermal conductivity of the soil.