ICF construction is the building of a residence or commercial structure using Insulated
Concrete Forms (or Insulating Concrete Forms). In ICF construction, hollow blocks are
stacked like bricks to form the walls of the structure, then reinforced with steel (rebar)
and filled with poured concrete.
This differs from more traditional wood frame wall construction where the walls are
constructed and insulation, usually fiberglass is added between the walls. There are
many different companies that manufacture the blocks used in ICF construction.
The process of building with ICFs is a relatively simple one. Many manufacturers of
Insulated Concrete Forms offer training that would allow you to become a certified ICF
installer for residential structures in one day.
What are the positives and negatives of ICF Construction?
There are some definite benefits to building a home with ICFs but I will start with the one
main negative, which is price. The price of a home using insulated concrete forms is
generally slightly higher than a house built with wood frame wall construction.
Prices will vary based on location and the relative price of wood and concrete at any
given time, but in general, a good estimate would be that the house using ICF
construction could be 3-7% higher in price.
A government study done in 2001 compared the monthly cost of a $200,000 standard
wood home to a comparable ICF home. They used a 7.5% interest rate with 20% down.
Then they added in taxes, insurance and energy costs.
The ICF home cost $208,000, which is a little more than 4% more than the wood home.
But because of the strength and energy-efficiency of the ICF home, there was a small
monthly savings on power and insurance over the wood framed home.
The total monthly costs in this example were $24 more a month for the ICF home, which
came to $1613 vs $1589 for the wood framed house. So with a small difference in price,
you can see why some people may be interested in checking out the benefits of
insulating concrete forms to see if ICF construction looks like a worthwhile investment.
Here are some benefits of ICF construction that may appeal to someone building a new
Safety and damage prevention from severe weather – The strength of reinforced
concrete has been shown to hold up very well in tornadoes and hurricanes, where the
wind can get up to 180 mph.
Energy Efficiency – I like the idea of using as little energy as possible and ICF walls are a
great way to conserve on heating and cooling. The price of energy can vary greatly and
in times of crisis when it is most expensive, the savings will be the greatest over homes
that are less energy-efficient.
Noise Control – If you have ever lived in a house near a busy road, or other source of
noise this may be a major selling point of ICFs.
Having lived in a house with inadequate insulation near a major road, I can tell you from
experience that it can be annoying at times. In addition to the noise from the traffic, in an
area like this people naturally talk louder to compensate for the constant noise so you
when your neighbors are outside talking you can hear everything that is going on, which
can also be distracting. A really nice feature of a home constructed with ICFs is that it is
extremely quiet, even in an urban location or one with other outside noises.
Fire resistance – Concrete is more resistant to fire than wood.
Less susceptible to insect or rodent damage – Chewing through 6 inches of concrete is a
deterrent for rats and you’ll definitely not have them living in your outer walls. Also
cement blocks are not a source of food for termites. (However, if you live in an area
where termites are prevalent you still need to take precautions, because termites can still
burrow their way to the wood parts of your house.
Given the benefits of building a house with ICFs, this type of construction is becoming a
reasonable choice when compared with traditional wood construction. It comes down to
whether the value added in the form of being in a quieter, more structurally sound house
outweighs the difference in price. Especially in places with a higher chance of strong
and potentially damaging winds, it is not surprising that many people are choosing ICF
If you’re interested in learning more about building with ICFs and seeing who uses this
construction method in your area check out the state pages for ICF builders. Also the
ICF Manufacturers websites all have very interesting information on safety and other
benefits of their products.
-Some calculations and other information came from a publication from the U.S.
Department of Health and Urban Development called "Costs and Benefits of Insulating
Concrete Forms For Residential Construction".
What is ICF Construction?