In their interpretation and application the provisions of this chapter shall be held to be the minimum requirements for the promotion of the public health, safety, comfort, convenience and general welfare. It is not intended by this chapter to repeal, abrogate, annul or in any way impair or interfere with any provisions of the law or ordinance or any rules, regulations or permits previously adopted or issued or which shall be adopted or issued pursuant to law relating to the use of building or premises nor is it intended by this chapter to interfere with, abrogate or annul any easements, covenants or other agreements between parties; provided however, that where this chapter imposes a greater restriction upon the use of buildings or land or upon the height of buildings or requires larger yards or other open spaces than are imposed and required by such existing provisions of law or ordinance or by such rules, regulations, easements, covenants or agreements the provisions of this chapter shall control and where a greater restriction is provided by other ordinance or otherwise, such greater restriction shall control.