Strange as it may seem, there are some people in this world who do not know what ICF means. Let me help change that. ICF is an acronym that stands for Insulated Concrete Forms. Basically these are stacking styrofoam panels with webs spreading them apart. When the blocks are stacked up according to design, they create a hollow wall with styrofoam on the inside and the outside. This has reinforcing rod placed in it, then is pumped full of concrete to create a solid, insulated, concrete wall.