Any building, extension or alterations for which a permit has
been duly granted, the construction of which has been started before
the effective date of this chapter or of an amendment thereto, and
the ground story framework of which, including the second tier of
beams, has been completed within one year after the adoption of this
chapter or an amendment thereto, may be completed in accordance with
plans on file with the Code Enforcement Officer, provided that such
construction is completed within one year of the adoption of this
chapter or an amendment thereto. If any of the requirements shall
not have been fulfilled within the prescribed period or if the building
operations are discontinued for a period of six months, any other
construction shall be in conformity with the provisions of this chapter.