Quote Originally Posted by Timothy Miller View Post
Howdy, the 2" 24 " wide foam insulation board is laid onto the soil and easily covered with mulch or stone etc. It makes not having to insulate the walls of the basement as it moves the freeze/ frost zone away from the foundation. The book i was reading was making the point that it brings the average 58* earth temp at 8' below grade up for lack of a clearer explanation and moves the heat sink away from the outside wall of the foundation.
Some are using with crushed stone shallow foundations ....
Thanks for the information about the spray foam too.
Huh ?!?!
Sorry ---- there's no way that simply laying a 2 inch thick by 24 inch wide sheet of rigid foam flat on the ground beside the foundation is going to prevent the frost penetrating below that sheet of foam.
You would need a vertical thermal break from the rest of the soil the entire 8 feet down.