Post by Watts Radiant on Jul 7, 2010 6:27:47 GMT -6
Typically, if a wall is below grade, we do not take into account the heat flux through that wall. The heat loss through a wall into the soil is minimal in the grand scheme of things.
If the wall is partially below grade, just add a wall and specify the total area of that wall that is above grade. So, if you have a 100sqft wall, and it's 1/2 below grade, you'd specify a wall that's 50sqft.