Single family homes, duplexes and townhouses shall all be treated as Single Family Residential (SFR) for the purpose of compliance modeling and registry project types. Other low-rise residential buildings shall be treated as Multi-Family Residential (MFR).
NOTE: A duplex or townhome (an R-3 occupancy) must be modeled as multiple single-family buildings. Each dwelling unit will be a separate input file rather than modeling a building with multiple dwelling units.
Low-rise residential buildings include all single-family dwellings and multi-family buildings with three or fewer habitable stories throughout the entire building. The three-story designation relates to multifamily buildings, since all single family homes fall under the low-rise residential requirements regardless of the number of stories. An apartment building with three or fewer habitable stories falls under the low-rise residential standards while an apartment building that has more than three habitable stories falls under the nonresidential standards.
A townhouse is a single-family dwelling unit constructed in a group of three or more attached units in which each unit extends from the foundation to roof and with open space on at least two sides. A townhouse may have common walls on either side but may not have common ceilings/floors. A duplex is a special case of a townhouse that may be configured to have a common wall or floor/ceiling.