Strength Comfort Affordability



Building with E-Z Block creates a quality home, and you will notice the difference.

In a 1997 survey, interviewers asked owners of 74 new ICF homes and 73 new wood frame homes what they liked about them. Over 80 percent of the ICF owners mentioned the great comfort, compared with 22 percent of the wood frame owners.

Over 60 percent of ICF homeowners mentioned the quietness of their homes, versus only 2 percent of the wood frame homeowners. The ICF owners told two common stories over and over again:

“I looked out the window and saw the traffic on the road, but I couldn’t hear it.”

“While talking with my neighbor one morning, he asked if the thunderstorm the night before woke me up, too. But until that
moment I never even realized we’d had one.”

The energy efficiency of E-Z Blocks is attributable to three factors:

1. Consistent R-Value


E-Z Blocks provide consistent insulation with a solid structure and no risk of deterioration over time. Wall studs with very low insulation take up approximately 11% of your wall. Fiberglass insulation runs the risk of sloppy installation and sagging over time.

The high performance of E-Z Blocks simply cannot be matched by traditional framed construction. The R-Value claimed by wood frame houses is based on laboratory testing of insulation. It does not take into account the real world performance of the overall wall. Insulation can easily have variations in thickness and even gaps due to poor installation. Wall studs, which have extremely low insulating properties, provide a ‘thermal bridge’ for heat to infiltrate or escape.

2. Reduced Air Infiltration

Over half of a framed homes energy loss is due to air infiltration and heat loss through the wall assembly. Air infiltration is typically around .5 ACH (Air Changes per Hour) This means that every hour half the the air volume in a framed house is exchanged for outside air that needs to be heated or cooled.

Our solid insulating blocks locked together with continuous concrete make E-Z Block walls exceptionally airtight. In tests, homes built with ICF’s had only about 1/3 to 1/2 as much air infiltration as the typical frame house.


3. Thermal Mass Effect

R-Value measures a materials resistance to heat flow. These values are measured in carefully controlled testing laboratories. In real life there are other factors that determine the overall energy efficiency of your wall. One of these factors is your walls heat capacity. Heat Capacity measures how much heat a material can hold, and is most significant with heavy, high-thermal-mass construction, like E-Z Block walls. E-Z Blocks concrete core provides excellent heat absorption and ‘thermal lag’. This, combined with the insulation of the block itself serves to reduce and delay peak loads, which may result in low off-peak energy pricing and reduced HVAC equipment sizes. E-Z Blocks moderate internal temperature swings and reduces the amount of heating or cooling needed.

Another benefit of thermal mass is heat flow reversal, which happens when the temperature outside fluctuates above and below your target temperature in a 24 hour cycle.


As the day begins, heat transfers into the exterior of the wall Throughout the day the insulated walls slow the heat flow, while the high thermal mass stores the heat that does get through As the outside temperature drops the direction of heat transfer reverses, sending the stored heat back outside rather than to the interior.

Taking the thermal mass effect into consideration yields a mass-enhanced R-Value, or Effective R-Value. This is calculated by multiplying the steady state R-Value by the DBMS (Dynamic Benefit for Massive Systems), which has been calculated for different climates by researchers at Oak Ridge National Laboratories.

E-Z Block Effective R-Value