My builder doesn’t want to use ICFs, but I’ve heard they’re a great product. What do you think?

Asked by George Matthews, Walnut Creek, CA

The custom green builder I'm working with tells me Insulating Concrete Forms (ICFs) are not a good product. He did not say why, but he is opposed to using them. His opinion is contrary to what I have heard in other green-building circles. Could you give me your take on whether ICFs are a good choice for my future green house?


Daniel Glickman

Answered by Daniel Glickman

Sherborn, MA

Sustainable Construction Services, Inc.

May 21, 2009

Insulating Concrete Forms are a fantastic invention. They are most often used to build high-performance, durable basement wall structures with the potential of cutting costs.

  • ICFs typically involve a certain setup cost and are more expensive than conventional forming.
  • In a new-construction setting, the extra investment pays off in labor and material savings (costs are reduced, for example, by the fact that ICFs are often drywall ready).
  • But when building an addition on an existing structure, there is little benefit to the extra cost. I have found that on my remodeling jobs ICFs were just not a cost-effective or desirable option.

ICFs are a good product for new construction, but I advise you not to try and force a builder to use a technology they are not comfortable with.

  • ICFs are not the only way to build a good basement, and many builders are not experienced with this technology.
  • Focus on finding a builder you trust. Then listen to their rationale; if they have an honest reason for not choosing ICFs, you should respect that and move on.

Tagged In: icf, residential foundation

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