Off-street parking spaces shall be provided and kept available as an accessory use to all uses of buildings, structures and lots in amounts not less than the following:
A. 
For residential uses: two improved parking spaces for each dwelling unit.
B. 
For office or commercial uses: one paved parking space for every 200 square feet of floor area contained in the buildings or structures devoted to such use.
C. 
For industrial uses: paved parking area equivalent to the total ground coverage of the use, with a minimum of two spaces per each three employees.
D. 
For hotel or motel uses: one paved parking space per guest bedroom plus one per three employees.
Any application for a building permit where five or more parking spaces are required shall be submitted to the Planning Board for site plan approval before issuance of the building permit. In approving the site plan, the Planning Board shall require curbs, paved sidewalks, drainage facilities, in accordance with specifications approved by said Board as adequate to serve the property and use involved, and may require adequate lighting to assure public safety and appropriate screening for the protection of adjacent properties when determined to be in the public interest.
Accessory off-street parking areas shall be marked off into parking spaces with a minimum width of 10 feet and a minimum length of 18 feet, or, in the case of parking spaces for trucks or special equipment, parking spaces of a minimum size to be determined by the municipality based on the nature of the parked vehicles.
The provisions of this article shall not apply to any building or structure or lot lawfully in use at the effective date of this article, whether continued as such use or thereafter converted or changed without enlargement to a different lawful use having the same parking requirements. However, no building or structure or lot lawfully in use at the effective date of this article shall be enlarged unless the off-street parking space requirements of this article are complied with to the same extent as would be required if the entire preexisting building or structure or lot and the proposed enlargement were being submitted as if it were a new application for a building permit for the entire project.
The Board of Appeals may waive the requirements, in whole or in part, for the off-street parking spaces stipulated in this article if it finds that practical difficulties or unnecessary hardship exist in a particular case and that such waiver will not unduly burden the existing parking facilities in the area and that no other suitable and adequate lot can be reasonably put to such use within 500 feet of the premises involved.