The NH Office of Energy and Planning publication, The Board of Adjustment in New Hampshire January 2005 gives detailed instructions on Nonconforming Uses. Some of this information is printed below. (For additional information see pages 20 - 23) complete copy of this manual (104 pages) is available from the NH Office of Energy and Planning at www.nh.gov/oep/resourcelibrary/HandbooksAndOtherPublications.htm
A zoning ordinance adopted under RSA 674:19 shall not apply to the existing use of any building. It shall apply to any alteration of a building for use for a purpose or in a manner which is substantially different from the use to which it was put before alteration.
"A nonconforming use is one that was lawfully established before the passage of the provision in the zoning ordinance that now does not permit that use in that particular place. Nonconforming uses enjoy constitutional protections under state law which allow them to expand to a certain degree.
A legal test for expansion of nonconforming uses has been established by the NH Supreme Court from cases such as New London Land Use Assoc. v. New London Zoning Board. 130 N.H. 510 (1988).
In reviewing whether a particular activity is protected as within the existing nonconforming use, the following factors, or tests, must be considered:
To what extent does the challenged activity reflect the nature and purpose of the existing nonconforming use?
Is the challenged activity merely a different manner of utilizing the same use or does it constitute a use different in character, nature and kind from the nonconforming use ? and
Does the challenged activity have a substantially different impact on the neighborhood?
In order to be allowable as a "natural expansion," expansion of a nonconforming use must not be such as to constitute an entirely new use. Factors to be considered are the nature and purpose of the prevailing nonconforming use, the nature and kind of the proposed change in use, and whether the change in use will have a substantially different effect on the neighborhood. (Devan v. Windham., 132 NH 302 ,1989)
Because nonconforming uses violate the spirit of zoning laws, any enlargement or extension must be carefully limited to promote the purpose of reducing them to conformity as quickly as possible.
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