Date: August 21, 2017

Thermal Mass Effect of an ICF Wall

ICF construction, insulated concrete forms

How long does it take for the heat to turn on when an ICF wall is exposed to a frigid 31°F? Two hours? Three hours?  

What would you say if the answer was two entire days?

Here are the details of a test that was performed by an Insulated Concrete Form (ICF) manufacturer.

An R-24 ICF wall was placed in the middle of a test chamber. The temperature on one side of the chamber was reduced to -31°F while the temperature on the other side was maintained at 70°F by a heat source.

Amazingly, for two entire days, the thermostat did not detect a temperature drop and the heat never turned on.  Then, for days three and four, the R-24 ICF wall operated at an amazing R-45* to R-82* and for the ten remaining days of the test, the ICF wall operated from R-45* and gradually tapered down to its actual R-24 R-value on day 14 where it remained thereafter.

This is the thermal performance boost created by the “thermal mass effect” of an ICF wall. 

If you are currently working on a project and would like free project design and technical assistance to convert your project to ICF construction, contact a Chaney Enterprises sales representative or call us at 800-424-2639.    

*Instant apparent thermal resistance over time, simplified calculation.