Building Energy Fundamentals


The fundamental modes of heat transfer are conduction, convection, and radiation. Each are important for building design. A representation of convection and radiation are shown here.


Understanding heat transfer fundamentals and how they translate into energy flows in a building is critical when designing high performance buildings. Learn about the different forms of heat transfer, material properties like U-factor and R-value, heating and cooling loads, energy use intensity, and the difference between site and source energy. Constructing and operating buildings requires energy, but high-performance buildings use the right blend of passive and active design strategies to minimize this energy use while keeping people comfortable.



Heat Energy Flows in Buildings

Understanding heat flows is key to creating energy efficient buildings. Understand latent heat vs. sensible heat and how heat is transferred via conduction, convection, and radiation.

Thermal Properties of Materials

Every material has fundamental material properties that determine their energy performance like conductivity, resistance, and thermal mass. Knowing these terms will help you chose the right materials to improve heat flows.

Building Energy Loads

Energy loads are how much energy your building needs. These demands can be provided by electricity, fuel, or by passive means.  Thermal heating and cooling loads are also important concepts that drive how much energy the building’s HVAC system will use.

Measuring Building Energy Use

Knowing how to measure energy use in buildings will help you set better energy efficiency goals. Energy Use Intensity (EUI) normalizes energy use by floor area and is useful for targets and benchmarks. But, when it comes to environmental impacts, you need to look upstream at “source energy.” Also, when it comes to energy efficiency measures, you need to know what end-uses take the most energy.