Insulated Concrete Forms, or better known as ICF blocks, are a stay-in-place concrete form that interlocks together. These concrete forms are becoming the leading way of building, as they create an air-tight envelope against vapour leaks and conductive/non-conductive heat loss.  ICF blocks come in different *R-values, but once these forms are filled with concrete they can boast far greater R-values because of the concrete’s thermal mass. The result is energy savings well over 50% when compared to conventional building methods.