Celebrating 75 years!

Optimize Energy Performance and Thermal Storage

To reduce the environmental and economic harms of excessive energy use by achieving a minimum level of energy efficiency for the building and its systems.

  • Moderate indoor temperature
  • Reduce heating and cooling loads
  • Shift peak heating and cooling loads to off-peak hours
CalGreen 5.201.1
CHPS EE 1.0 Prereq.: 8 pts.; EE 1.1: up to 40 pts.
GGlobes up to 180 pts.
BDCv4 EA Minimum energy performance: Prereq.;
Optimize energy performance, Op 1: up to 18 pts. (Healthcare 20 pts., Schools 16 pts.)
BDCv4.1 EA Minimum Energy Performance: Prereq.;
Optimize Energy Performance, Op 1: up to 18 pts. (Healthcare 20 pts., Schools 16 pts.)
NDv4 GIB Minimum building energy perf.: Prereq.; GIB Optimize building energy per.: up to 2 pts.
RELi HA Req. 3.0 Fundamental Emergency Operations: Thermal Safety (Passive Survivability)
HA Credit 3.0 Passive Thermal Safety
EW Req. 2.0 Minimum Energy Efficiency + Atmospheric Impacts
EW Action 4.1 Energy Optimization
Products /
  • Concrete unit masonry

Concrete masonry can harvest site energy using passive solar designs and decrease the size of HVAC systems. It has high thermal mass and specific heat, providing very effective thermal storage. The result is a beneficial lag between peak heating and cooling loads and outside temperature peaks, thereby delaying needed heating or cooling and lowering associated energy demand.

Interior walls act as heat-sinks to moderate indoor temperature swings, further reducing heating/cooling loads. Whole-building analysis programs capable of projecting a building's energy use and cost based on an hour-by-hour simulation can accurately model concrete masonry's thermal mass and predict associated savings.

Concrete masonry's thermal mass is a resiliency feature and a potential for RELi's Thermal Storage Wall.

The California Energy Code recognizes the value of heavy mass walls (with concrete masonry units (CMU) in its definition); for most metro areas in Southern California, no insulation is required..

Please see California Energy Code References, a quick reference guide to concrete masonry in the energy code.

Optimize Energy Performance