Insulated Concrete Forms

            Concrete Forms, or ICFs as they are more commonly known, are lightweight foam forms that do double duty. When a concrete wall is first poured, the forms are used to provide the support necessary for proper concrete curing. Once the curing process is complete, the forms are allowed to remain in place in order to provide thermal insulation. The ultimate result is a truly extraordinary concrete wall that is superior in many ways to other, more common wall types.
             Common ICF Materials.
             ICFs are generally made using one of two types of foam: expanded polystyrene (EPS) or extruded polystyrene (XPS). EPS is relatively inexpensive, known to provide reliable protection from moisture and air, and available in molded form and sheet form. XPS, which is a more expensive material, has a greater R-value than EPS, is slightly more resistant to moisture and air, and is usually available in sheet form only.
             Construction.
             Most often, ICFs are made by pouring concrete into hollow foam blocks or panels. The forms, which are stacked onto specially engineered footers and held in place by reinforcement bars and braces, are then allowed to cure for a few days. After the curing process is complete, interior finishes like drywall and exterior finishes like stucco and brick are affixed. Electrical wires are sometimes channeled through the ICF's foam surface to accommodate design specifications.
             Why ICFs?.
             Although the benefits of using ICFs are many, three generally top the list: .
             Energy Efficiency. According to the builders" best practices section of HGTV.com, homes built using ICFs require 30% to 40% less energy for heating and cooling than those using wooden frames.
             Lower Construction Costs. Because concrete is a thermal mass material, ICFs help to mitigate temperature swings in the home and effectively eliminate drafts and cold spots. As a result, builders can often install HVAC systems that are smaller than those used for other projects, saving $500 to $2,000 in the process.