Insulated Concrete Foundation Systems

Insulated concrete foundation systems,  basically foam forms filled with concrete. The results of using this system is dramatic, in the reduction of temperature swings within the structure. If this system is used to build the exterior walls of the house as well as the foundation, the energy needs are further reduced.

Benefits

        The principal is a simple on of thermal mass. The walls of the house act as thermal mass, which stores the thermal energy surrounding it. I had the opportunity to see the effects first hand. A house I am currently working on has this wall system. The heating system for the radiant floor was installed on a Tuesday afternoon. Sometime during the first night of operation the system shut down. Upon arriving on Wednesday morning, I found the home heated to 67 degrees F, and the system not running. I called the heating installer, to apprise him of the situation. Being the day before Thanksgiving, he would not be able to fix the problem until Friday afternoon.  I closely observed the temperatures over the next several days. Although it was not that cold, Wednesday's high temp 45 F, Thursday's high temp 50 F and Fridays high temp of 31 F. The house only dropped 3 degrees F over the course of the 3 days without heat. The heating installer was astounded when he arrived Friday night to find the temp. 64 F, and had to adjust the temperature of the radiant floor heating lower to prevent overheating of the building.

Liabilities

         This type of construction cost more to build than traditional construction. It also requires specialized skills to install this system. The ICF ( insulated concrete form) manufacturers and installers will have you believe the cost increase is small. The true picture is that this system impacts other building components and increase their costs as well. For instance siding, how do you attach wood siding to foam insulation. Wall thickness is increased having an impact on finishing materials on the interior of windows and doors. Most electricians are unfamiliar with the techniques used to install electrical wiring, and usually charge more if they are unfamiliar with installation methods.

Cost benefit analysis

        I am currently working on a design for a zero energy home, and I am doing a cost benefit analysis of this system in comparison to SIP's. When this CB analysis is complete I will post it here on this page.

        This is one option that is defiantly worth doing, if you intend to use your basement as living space.

       

This was a hybrid house using ICF walls and SIP roof and gables.