No building shall hereafter be erected, and
no existing building shall be moved, structurally altered, rebuilt,
added to or enlarged, nor shall any land be used for any purpose other
than those included among the uses listed as permitted uses in each
zone district of this chapter and meeting the requirements set forth
herein. Open space contiguous to any building shall not be encroached
upon or reduced in any manner except in conformity with the area and
bulk requirements, off-street parking requirements and all other regulations
required by this chapter for the zone district in which such building
or space is located. In the event of any such unlawful encroachment
or reduction, such building or use shall be deemed to be in violation
of this chapter, and the certificate of zoning compliance shall become
null and void.