Myths and Misconceptions ICF walls feature steel reinforced concrete, giving them far greater strength than CMUs. Affordability of an ICF Home

The True Cost of an ICF Home

ICF Construction Cost

When building your own home, On average, new houses built by experienced contractors cost about 3-5% more than conventional 2×4 wood-frame houses of the same design. However, there are cost savings in other areas that will help to offset some of these first costs. Choosing to build with ICFs will provide the homeowner with significant improvements in day to day operational expenses and environmental impacts.

Since ICF homes are more energy-efficient, mechanical equipment can be smaller than in a frame home. This can typically result in at least 1% in up-front savings. So the net extra cost will be about 3 to 6% of the sale price of the home.

Higher quality exterior walls and smaller mechanical systems mean less monthly cost for the homeowner with savings of at least 25% or more depending on the climate. Downsized HVAC also results in reduced greenhouse gas emissions over the life of the structure compared to less efficient wood-frame construction.

An ICF Home Saves You Money

An important cost for homeowners to consider is the monthly utility bill. ICF homes are much more energy-efficient and cost far less to maintain compared to wood-frame homes.

ICF walls are made of solid, steel-reinforced concrete that is insulated on each side by EPS foam to create a highly energy-efficient thermal barrier that has 58% better overall R/RSI-value than the insulated wood-frame cavity walls.

While the EPS foam works as effective insulation it’s the thermal inertia of the concrete core that adds the greatest advantage. Concrete is a dense and heavy material that is resistant to temperature change. This prevents both exterior and interior temperature changes from affecting the wall temperature on the other side. Whether it’s hot or cold outside, an ICF home can maintain a stable and comfortable temperature at a fraction of the cost.

On average, the monthly utility cost for a wood-frame home is $0.10 per square foot, whereas the average ICF home costs only $0.03 per square foot. Wood-frame houses might cost less to build, but the larger utility bills outweigh the initial savings in the long run.

Consider this comparison between a wood-frame home and an ICF home. In this example, both homes are 2,500 square feet, and costs are calculated with a 2% inflation rate over a span of 30 years.

30 Year Cost Summary

 Wood-Frame Home

ICF Home

Total Mortgage Cost$375,584$422,536
Total Utility Cost$106,650$31,995
Total Cost$482,235$454,531

After 30 years, the ICF home saved $74,655 on utility costs which more than makes up the difference in mortgages.

In addition to the energy efficiency and utility cost savings, ICF homes feature far more benefits for the owner.

More Than Just Savings

Each year, the number of new home buyers who choose to have their houses built with concrete and ICFs continues to increase. Saving on the cost of fossil fuel consumption, and reducing emissions is a huge plus. In addition, they also cite these additional advantages:

Comfort

ICF houses are far less drafty than wood-frame homes, resulting in far fewer “cold spots”, and maintain a more stable temperature.

Quiet

Only about one-sixth as much noise travels through an ICF wall. Occupants are pleasantly surprised by the reduction in noise that enters from outside.

Strength

Owners of ICF houses feel less flex in their walls and floors. They notice virtually no vibration when they slam a door. Engineering calculations show the walls are much stronger than frame walls in many ways. Field data show they survive many types of natural disasters better.

Energy Efficiency

ICF walls cut an estimated 30-40% off the energy used to heat and cool a house. ICFs create a thermal barrier that outperforms traditional construction.

The Quality of Concrete Costs Little More

The many benefits of a concrete house built with insulating concrete forms (ICFs) are available for only slightly more than the cost of traditional wood-frame construction. ICFs are simple to assemble and they consolidate several construction steps into one. This means that the walls can be economical despite the use of high-quality materials.

The cost of ICF Construction by component.

Cost Comparison

When building with ICFs, proper planning and design mitigate most of the cost difference. Currently, ICFs cost 3-5% more to build a comparable size home, depending on the manufacturer and other factors impacting local building costs. Most importantly, the increased construction costs are being offset by significantly lower utility bills.

Houses built with ICF exterior walls require an estimated 44% less energy to heat and 32% less energy to cool than comparable frame houses. The bigger the house, the bigger the savings. In colder areas of the U.S. and Canada, heating savings will be more and cooling savings less. However, in hotter areas, heating savings will be less and cooling savings more.

What is an “experienced contractor”?The more experienced your ICF installer, the lower the cost of using ICFs becomes.

As with any innovative new construction product, the more a crew works with ICFs the more efficient assembling them becomes. ICF wall-building crews report that their costs drop sharply until they have built 4 or 5 houses. After that, they continue to realize savings but at a slower rate.

Also, be sure to consider that mechanical contractors also need experience to size equipment correctly. If not experienced with homes as energy-efficient as an ICF house, they will tend to install equipment sized for a wood-frame residence. However, systems larger than necessary do not run efficiently and the buyer loses potential initial day-to-day cost savings. Thankfully, helpful computer software is available for correctly sizing heating and air conditioning systems in concrete homes.

Will homeowners save money living in an ICF home?

Because ICF walls feature thicker unbroken layers of insulation and the mass of concrete, they provide much better energy performance than conventional wood frame construction. Computer simulations comparing concrete homes to wood frame construction have shown the combined effects of higher R-values, low air infiltration and the impact of concrete’s thermal mass all combine to enable concrete walls to provide significant operating cost savings. Savings will vary by climate with the inherent thermal mass benefits having more impact in warmer locations and the added insulation being more critical in colder areas.

Click for more information about ICF energy savings.

How can living in an ICF home reduce greenhouse gases?

Life cycle studies show most of the environmental load of a typical home is from the household use of natural gas and electricity during the life of the house. Enclosing a home with more efficient ICFs means less mechanical equipment and fossil fuel consumption during the life of the house. This also means that the concrete house will generate fewer greenhouse gases than a comparable wood frame residence.

Click here to learn more about ICF green practices and sustainability here.

What’s the bottom line?

Lastly, when planning a new house, you can estimate that building the walls of concrete with ICFs and experienced crews will add about 3 to 6% to the overall cost of an ICF home. The high performance of the ICFs will provide the concrete homeowner with significant reductions in energy consumption and emissions while providing a stronger, quieter, and more comfortable home.


1. “RSMeans Residential Cost Data,” Reed Construction Data, Inc.
2. “Energy Use of Single-Family Houses With Various Exterior Walls,” by CTL Group for Portland Cement Association, 2001, PCA CD026.
3. “Comparison of the Life Cycle Assessments of an Insulating Concrete Form House and a Wood Frame House,” by CTL Group for Portland Cement Association, 2008, Serial No. 3041.

Source: Portland Cement Association Technology Brief 5

Affordability of Building with BuildBlock ICFs October 8, 2012