What and Why ICF?

ICF is the abbreviation for Insulated Concrete Form. You have probably seen walls of expanded polystyrene (similar stuff to the insulated white coffee cups you have used) being erected here and there; these are ICF structures. Reinforcing steel is placed as specified during the stacking process, openings are formed in a variety of ways, concrete is then placed in the wall forms and vibrated for proper consolidation. The EPS foam that creates the form stays in place, providing superior insulation. Result, a great wall!

There are over sixteen manufacturers of ICFs, so you have plenty of options. Generally all ICFs provide similar results to the owner: the structures built with this technology are very strong, very quiet, very energy efficient. Looking from the street there is no difference between an ICF house and a conventionally constructed house. Only when one steps inside and feels the quiet, sees the deep windowsills (the walls are typically 12” thick), senses good shelter, is the difference evident. These buildings typically reduce heating and cooling costs by 35 to 45%.

Concrete structures are extremely long lasting and provide secure shelter to the occupants. The primary ingredients of concrete - stone, sand and water- account for 90% of the mixture and are plentiful in most locations. The concrete and foam forms are 100% recycle-able. There are trained and experienced installers and contractors working with ICFs in Pagosa Springs, Durango, Cortez, and all of Colorado. Framers, carpenters, masons, concrete subs, homeowners and builders have all installed ICFs with great success; this is an additional skill-set, not a replacement skill.

Why ICF? 

Study the following chart.

	ICF	Wood-frame
R-value	22 +	R-11 to R-19
Effective R-value	up to R-50	R-9 to R-16
Heating & cooling/YR	$480-600	$1600-2200
Air leakage	.07 ACH	.4 ACH
Drafts	No	Yes
Even temperatures	Yes	No
Noise reduction	STC 50	almost none
Pollen infiltration	No	Yes
Wind resistance	200 MPH+	80-100 MPH
Fire rating	4 hours+	None
Bulletproof	Yes	No
Rodent proof	Yes	No
Nail pops	No	Yes
Wood rot	No	Yes
Wood splits & warps	No	Yes
Promotes mold growth	No	Yes
Qualifies for higher loan	Yes	No
Appraisal advantage	Yes	No

So, why WOOD you?

More about ICFs

The first ICF patent in the USA was issued in 1968. Our construction industry is not known for its rapid adoption of new technologies, so though the original Foam Forms® were used into the 1980s, when more recent designs began to shoulder Foam Form® aside, their use was rare and largely unnoticed. In 1985 Lance Berrenberg began manufacturing Southwest Foam Forms in Albuquerque; that company became American Polysteel and is still in business, though under a new name since the company has been acquired. Other early forms such as Greenblock and Lite-Form are also still being manufactured.

The bulk of ICFs are manufactured 4’ long by 16” tall in varying core thicknesses. A latecomer to the industry is NUDURA, a form that is 8’ long and 18” tall. Most ICFs are installed horizontally but a few systems, such as TF System believe their vertical forms are preferable. There are other stay-in-place forms, not wholly made of polystyrene, such as Rastra and Durisol and each makes its claim as a better product.

In 2006 ICFs were being installed at a rate of about 120 million square feet per year; this number has been expanding at about 20% per year.

Concrete may be recycled (look at ex-Stapleton airport landing strips & runways, all recycled), and is extremely long lasting.

About the Author:

Felix Marti began his construction career in 1964 and has specialized in energy efficient, low maintenance structures; he is now retired from construction. Mr. Marti states that he believes ICF construction will become the technology of choice within the next ten to fifteen years, whether the structure to be built is a hospital, a home, a school, or a theater; virtually any space to be heated or cooled.may be reached at 970-626-4169 or fmproventech@me.com.