MODEL BYLAW FOR ACCESSORY DWELLING UNITS

Introduction
Accessory dwelling units (also known as ‘accessory apartments’, ‘guest apartments’, ‘in-law apartments’, ‘family apartments’ or ‘secondary units’) provide units that can be integrated into existing single family neighborhoods to provide low priced housing alternatives that have little or no negative impact on the character of the neighborhood.

The regulatory approach used by most municipalities for accessory dwelling units is a zoning bylaw that permits an accessory unit, thereby allowing certain improvements to be made to the existing dwelling. Provisions can address certain restrictions based on whether the dwelling existed as of a certain date, the maximum allowed building and site modifications, the options for choosing inhabitants, whether the main unit needs to be owner occupied, and minimum lot sizes. However, the greater the number of restrictions, the fewer options there are available to homeowners for adding the units.

The following is a model bylaw for accessory dwelling units. It is recognized that there is no single “model” that can be added to community regulations without some tailoring, therefore revisions to the text within this model is encouraged. There may also be a need to examine local development review process to find ways that the process can be streamlined to encourage homeowners to use the accessory dwelling unit ordinance.

The annotation included in this model bylaw will not be part of the adopted bylaw, but will serve as a “legislative history” of the intent of the drafters and the interpretation to be given to certain terms and provisions. The annotation includes some recommended positions that reduce burdens on both homeowners and municipalities when implementing the bylaw.

Continue reading the full ADU Model Bylaws – http://www.mass.gov/envir/smart_growth_toolkit/bylaws/ADU-Bylaw.pdf