Questions, Answers & General Information

Why is it important to sandwich insulation between two layers of concrete?
(This is our CAST-TILT sandwich panel.)

Concrete provides thermal mass. That is, the concrete is able to store significant amounts of thermal energy and delay temperature transfer through the building walls.

According to the Fundamentals Handbook of the American Society of Heating, Refrigeration and Air Conditioning Engineers, Inc. (ASHRAE), this delay leads to three important results: First, the slower response time tends to moderate indoor temperature fluctuations under outdoor temperature swings. Second, in hot or cold climates, energy consumption is reduced over that for a similarly sized low-mass building. Third, building energy demand can be moved to off-peak periods because energy storage is controlled through correct sizing of the mass and interaction with the HVAC system.

Other benefits of this wall design include a tough, durable surface that resists mold, rot, insects, and fire and substantially reduces noise transfer, building maintenance, and more.

Is a sandwich wall the most energy efficient wall system?

Probably not. According to several studies completed by the Oak Ridge National Laboratory and other associated laboratories, the sandwich wall performs well but trails slightly behind the performance of the interior mass wall system (our CAST-TILT SW panel). According to several energy studies conducted to demonstrate the potential of reducing energy consumption in residential buildings, “It was observed and documented that heating and cooling energies in massive houses can be far lower than those in similar buildings constructed using lightweight wall technologies.” [Read the Oak Ridge National Laboratory report.]