Insulated concrete forms (ICF) are a well-established technology used in various construction projects, ranging from traditional single-family homes to large commercial structures. If you're in the process of planning a new house, then it's likely that you're looking at wood frame (or stick-built) construction, but this isn't the only option. ICF offers a potential energy-saving alternative.
What Should You Know About ICFs?
Don't feel bad if you haven't heard of insulated concrete forms before. Although contractors have used this construction technique since the 70s, many home builders and potential homeowners may still be unaware of its benefits. Unlike a traditional stick frame construction, ICF uses precast foam forms for constructing a structure's walls.
When constructing a home using ICFs, installers begin by placing and connecting the blocks. Each block consists of an inner and outer wall separated by a polypropylene web. The central web acts as a support for the reinforcing rebar and also keeps the form walls in place. Once the blocks are locked together, contractors then pour concrete into the void.
Unlike other concrete forms, ICFs remain in place once the concrete has cured. This design method has several advantages that might make it worth considering if energy efficiency is a priority for your new home build.
Why Are ICF Homes More Energy Efficient?
Insulated concrete forms have three significant advantages that can make your new home significantly more green than a traditional wood frame design:
- Thermally isolated layers
- No air gaps
- High material R-values
Since a central layer of concrete separates each form's inner and outer walls, there's no direct contact between interior and exterior surfaces. In a wood frame, the studs act as a thermal bridge that can allow heat to travel from one side of the wall to the other. This effect results in potentially hotter summer interiors and colder winter interiors, increasing HVAC load.
When combined with the total lack of air gaps within the walls and the naturally high R-values of the polypropylene insulation and concrete, ICF blocks can achieve extremely high insulation levels. Better insulation means you can keep heated or cooled air inside while resisting more thermal load from the exterior environment.
Although insulated concrete forms are not a panacea for energy efficiency, they can serve as an excellent base for a green home. Designing your new house with these structural elements in mind allows you to gain even more benefit from other energy-efficient design elements. If you haven't thought about ICF construction before, it may be well worth considering for your new home.