PUDs are municipal regulations that allow developers exemptions from certain zoning requirements in exchange for developing properties with desirable criteria. Some municipalities include PUDs within overlay districts. By allowing greater flexibility in the configuration of buildings on a site or allowing mixed usage of a site, a municipality can encourage more creative and efficient use of a space than is typically allowed in local zoning laws. It can also result in lower infrastructure costs and better coordination of development across an area.
Municipalities often have distinct residential zones for high-density, multi-family buildings and others for low-density single-family homes. A change in the bylaws could be made to allow single- or two-family homes to be built more densely. This practice may overlap with cluster or cottage development practices.
Zoning bylaws often set a maximum density level (number of homes permitted in an area) without regard for the size and type of those homes. Instead, more units could be permitted in the same area if they are physically smaller in some circumstances. This is often seen with accessory dwelling units (ADUs) or in senior housing, which can allow smaller unit sizes in exchange for shared community spaces within a development.