It is not intended by this chapter to repeal, abrogate, annul or in any way impair or interfere with existing provisions of other laws or ordinances, except those specifically or impliedly repealed by this chapter, or any private restrictions placed upon property by covenant, deed or other private agreement, unless repugnant hereto. Whenever this chapter imposes a greater restriction upon, including but not limited to, the use of buildings or premises or upon the height of buildings or lot coverage or requires greater lot area or longer yards or other open spaces than are imposed or required by such rules, regulations or permits or by such private restrictions, the provisions of this chapter shall control.