Using IAPMO’s Water Demand Calculator tool can result in energy, carbon, and water savings as compared to using traditional plumbing specification methods in plumbing codes, according to a study by Arup.
Arup compared the Water Demand Calculator with the Hunter’s Curve method that has been a long-time standard in both the Uniform Plumbing Code (UPC) and the International Plumbing Code (IPC) for sizing domestic hot water systems. The study examined four residential-use cases, including a single-family home, and six-unit, 45-unit, and high-rise multifamily residences.
Water savings ranged from 450 gallons to 71,000 gallons annually depending on the building size. High-rise residential buildings were found to have operational carbon savings between 73% and 84% for booster pumps and embodied carbon savings ranging from 20% to 41%.
IAPMO’s Water Demand Calculator predicts peak water demand for single-family and multifamily dwellings, removing the need for assigning fixture units to plumbing fixtures. Instead, the IAPMO tool calculates peak demand using algorithms based on building size.