How to Insulate Concrete Form Systems

Mark the outer edges of the walls onto the slab by snapping a chalk line on each side.

Place silicone caulk onto the slab in one corner. Lay the foam blocks onto the slab, working toward the center of the wall and adding adhesive as you go. Keep the blocks level as you lay them. When you reach the center of the wall, return to the corner and lay blocks onto the next wall. Repeat this until the first course of blocks has been laid.

Lay the second course of blocks, again starting in the corners and working toward the center of the wall. Stagger the blocks in this row so that the joints between the blocks in each course do not line up with each other.

Place fiber-reinforced tape onto the horizontal joints between the two courses of blocks along the corners to reinforce the blocks. Wrap the tape around the corners so that it extends 4 feet down the wall on each side of the corners.

Install wooden bracing against the outer corners of the form, if the system that you're using requires it. It's not necessary in every system, and how it's installed can vary by manufacturer, so follow the manufacturer's instructions for the system you are using. Use a hammer, nails and 2-by-4-inch boards to build the braces.

Continue laying blocks until the walls reach the needed height. Stagger each course of blocks as you lay them, and lay rebar horizontally inside the blocks, following local building codes. The foam sides of the blocks are held together by plastic tabs, which contain notches that can be used to hold the rebar.

Place vertical rebar inside the blocks after you have finished laying them, again following local building codes regarding the spacing of the rebar.

Place wooden bracing against the form on both sides of the blocks. This provides extra support as the concrete is poured. Follow the manufacturer's instructions when building the bracing.