Overheating in Hot Water- and Steam-Heated Multifamily Buildings

Apartment temperature data have been collected from the archives of companies that provide energy management systems (EMS) to multifamily buildings in the Northeast U.S. The data have been analyzed from more than 100 apartments in eighteen buildings where EMS systems were already installed to quantify the degree of overheating. This research attempts to answer the question, 'What is the magnitude of apartment overheating in multifamily buildings with central hot water or steam heat?' This report provides valuable information to researchers, utility program managers and building owners interested in controlling heating energy waste and improving resident comfort. Apartment temperature data were analyzed for deviation from a 70 degrees F desired setpoint and for variation by heating system type, apartment floor level and ambient conditions. The data shows that overheating is significant in these multifamily buildings with both hot water and steam heating systems.