Preexisting nonconforming structures and structures containing a nonconforming use may be extended or altered only if there is a finding by the Zoning Board of Appeal (permit granting authority) that such extension or alteration shall not be substantially more detrimental to the neighborhood than the existing nonconforming structure or use. The proposed extension or structural change must itself comply with the Zoning Bylaw.

In the event a nonconforming structure or a building or structure containing a nonconforming use is damaged or destroyed in whole or in part by fire or other casualty, it may within two years of the date of the demolition permit be replaced by a building or structure to be used for the same purpose as the one destroyed. The building or structure reconstructed shall not exceed in cubic content or footprint that of the original building. The use resumed shall begin within one year of the completion of such replacement or reconstruction. "Original building or structure," for the purpose hereof, shall be deemed to be the building or structure legally existing at the time of destruction.

Nonconforming one- and two-family dwellings shall be allowed, as a matter of right, extensions or structural changes which meet all current zoning requirements for setbacks, building coverage, lot coverage, height and use for a district in which they are located.

When, in its judgment, the public welfare and convenience will be substantially served and where the status of the neighborhood will be improved, the Zoning Board of Appeal (permit granting authority) may, after a public hearing and subject to such terms and conditions as it may impose, vary the application of this chapter as follows: Allow variance from the applicable provisions of this chapter if the permit granting authority finds that a literal enforcement of the provisions of this chapter would involve substantial hardship to the petitioner, financial or otherwise, owing to site-specific soil conditions, shape or topography of land or structures which do not generally affect the zoning district in which it is located and that desirable relief may be granted without substantial detriment to the public good and without nullifying or substantially derogating from the intent or purpose of this chapter.

The Zoning Board of Appeal (permit granting authority) shall hold a public hearing in accordance with the provisions of MGL c. 40A. The Zoning Board of Appeal (permit granting authority) shall give notice as required by MGL.

If the rights authorized by a variance are not exercised within one year of the date of granting of such variance, such rights shall lapse. However, the permit granting authority in its discretion and upon written application by the grantee may extend the time to exercise such rights for a period not to exceed six months. The application for such extension shall be filed with the permit granting authority prior to the expiration of the one-year period. If the permit granting authority does not grant such extension within 30 days of the date of application for extension, the extension shall be deemed denied.

No variance may authorize a use or activity not otherwise permitted in the district in which the land or structure is located. However, such variances properly granted prior to January 1, 1976, but limited in time, may be extended on the same terms and conditions that were in effect for such variance upon said effective date.[1]