Thermal comfort refers to the heating and cooling systems a building uses, and how well these systems keep a home livable for the residents. According to the EPA, 56% of energy use in U.S. homes come from heating and cooling, so choosing the appropriate combination of systems is crucial to sustainability. Additionally, the type of system can define the comfort of a house for residents and the quality of heating/cooling provided. The ecoMOD homes use traditional options such as furnace heat and air conditioning, but also utilize zoned ductless heat pumps and radiant floors to achieve maximum comfort with minimum impact.