density

Reducing or waiving impact fees for affordable housing projects. Impact fees are important for municipalities because they require developers to pay their fair share of the costs of providing public services to the new development. However, impact fees can be an additional barrier to developing affordable housing projects.

Allowing building proposals that fit within the specifications of local zoning policies to proceed "as of right", without additional review. Developers still need to secure a building permit and fulfill customary regulatory requirements, but the approvals process is generally less contentious and/or time-consuming than the process for proposals that require an exception from current zoning regulations.

Cluster developments are a permitted use in which density regulations are determined for an entire specified area instead of a lot-by-lot basis, allowing more smaller units to be constructed in the area. Cluster development allows the developer greater flexibility in designing projects but preserves the overall density in an area. This can naturally encourage the construction of low-cost and therefore more affordable housing units. Municipalities can also require affordable housing to be developed as a condition of approval for adjusting density requirements.

Municipal planning ordinances that allow developers to increase the maximum allowable development on a property in exchange for making a certain percentage of the housing affordable. May be incorporated into inclusionary zoning requirements

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.

Zoning bylaws that require unnecessarily large unit sizes can prevent developers from building smaller, more affordable housing units. Municipalities can adjust zoning requirements to allow for studios, or micro-units or compact units in some instances.

Zoning bylaws that require large minimum lot sizes  (≥2 acres per dwelling unit) require developers to purchase more land for each unit and these costs are ultimately passed on to homebuyers or renters. Towns can promote the development of new affordable housing by changing their zoning bylaws so that less land is required for each lot. 

Municipal planning ordinances that require or incentivize developers to set aside a certain percentage of affordable housing units for low and moderate-income residents.