How can I identify a home as ICF (Insulated Concrete Form) construction?
Monday, July 29, 2019
Most of the time, the seller or their realtor is going to tell you. It’s considered premium, green construction, and a selling feature. But once in while a seller is not aware of it, or the information is not provided—or provided incorrectly.
Although an ICF home is easy to recognize during construction, like in the photo above, it doesn’t appear any different from regular construction when completed, as in the photo below. So a closer examination will be necessary to determine if you are looking at ICF, especially since the exterior can be similar to EIFS (Exterior Insulated Finishing System) on wood frame construction.
Here’s a few points for identification:
• Exterior finish is usually synthetic stucco, with the characteristic slightly hollow sound when tapped because of the EPS (expanded polystyrene) underlay; but there is no weep screed at bottom of wall that is standard for most EIFS over wood frame. Even though synthetic stucco is the most common finish, an ICF wall can also be clad in any other standard siding material.
• The EPS forms may be visible in the attic at any areas of exposed wall and top of wall at trusses (if not covered by insulation).
• Wall will be about 12” thick, or more, with deep window sills, based on typical 6” core of reinforced concrete and 2-3/4” of EPS on both sides. Even thicker concrete and EPS is sometimes used.
• If you remove a receptacle outlet faceplate, there will likely be a some EPS visible in the cutout around the shallower than normal receptacle box, and the drywall is applied directly to EPS.
- Photos courtesy of www.icfhomes.com. Also, thanks to Henry DeWerth for assistance with this article.
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To learn more about exterior walls and structures, see these other blog posts:
How To Look At A House
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