Insulated Concrete Form FAQ’s

Here are answers to some of the most commonly asked questions about insulated concrete forms. Features FAQ’s about design compatibility, appearance, and comparisons to other innovative materials.

Q: Will conventional siding work with ICF walls?

A: Yes. You can finish the exterior of an ICF wall with siding brick, stucco, panels, or any other exterior finish currently on the market. The only limitation of an ICF wall is that, unlike cement block, you will need some kind of exterior finish.

Q: What does a completed ICF home look like?

A: Since ICF walls can be finished with conventional materials inside and out, there is little difference in appearance between an ICF home and a conventional home. The window sills and jamb extensions are deeper due to thicker walls, but few people can recognize an ICF home at first glance.

Q: Do ICF homes require special plans?

A: No. Any set of house plans can be used for an ICF home with slight alterations. Most ICF walls are thicker than conventional exterior walls, so this will need to be considered, but there is no need to purchase a separate set of plans or change the design of a home.

Q: Are there limitations to the height of an ICF wall?

A: No. A structural engineer should be consulted, as with any other means of construction that exceeds standard architectural regulations, but the capabilities of the material itself are limitless.

Q: Do ICF walls have problems with condensation (sweating)?

A: No. This belief was started by people who witnessed the forms weep moisture from curing concrete. A freshly poured ICF wall will appear to be sweating as the moisture in the concrete weeps through the expanded polystyrene, but an ICF wall’s resistance to heat transfer will significantly reduce condensation after the concrete has cured.

Q: Are Termites a problem with EPS foam?

A: Termites, and other wood boring pests, will not eat EPS foam, so they are not a specific problem, but the expanded polystyrene foam in ICF walls is not necessarily termite proof. Termites can borough through the foam to reach wood, and the same measures should be taken to protect the wooden aspects of an ICF home as with any other home.

Q: Does the EPS foam in an ICF system “off-gas”?

A: No. EPS foam is inert, non-toxic, and formaldehyde free making ICF walls a perfect fit for people with sensitivity to the quality of indoor air.

Q: Do ICF walls complicate the installation of utilities and wiring?

A: No. Utilities can be run through ICF walls by cutting a small groove into the interior face of the block with a hot knife. The EPS foam is thick enough to allow for standard electrical boxes. Duct work may need to be rerouted through interior walls, if not already designed that way.

Q: What are the advantages of an ICF system?

A: There are many advantages of an ICF system. Builders in Florida tend to focus on the structural ability to withstand the forces of a hurricane, but ICF homes also have lower energy costs (up to 70%), higher quality of indoor air, reduced noise infiltration, and reduced mold proliferation, all with less maintenance than a conventional home

Q: How do ICF walls compare to SIPs panels?

A: ICF walls have a higher R-value, lower noise infiltration, and are stronger than SIPs panel walls. Also, unlike ICF walls, Sips panel walls will begin to degrade if not properly maintained. ICF blocks are a more efficient, longer lasting material, and can be ordered with a significantly lower lead time than most SIPs panels.

Q: Can an ICF system withstand the test of time?

A: ICFs have now been around long enough to safely say that they will and have withstood the test of time. Most standing ICF homes show no signs of degradation. While conventional building methods estimate a lifespan of 25 years without maintenance, ICF systems estimate an excess of 100 years without maintenance before the system begins to fail.