When interpreting and applying provisions of this title, such provisions shall be held to the minimum requirements adopted for the promotion of the public health, safety, comfort, convenience and general welfare. Except as specifically provided in this title, it is not intended by the enactment of this title to repeal, abrogate, annul or in any way to impair or interfere with any existing provision of law, ordinance, or any rules, regulations or permits previously adopted or issued, or which shall be adopted or issued pursuant to law relating to the erection, construction, establishment, moving, alteration or enlargement of any building or improvement; nor is it intended by this title to interfere with or abrogate or annul any easement, covenant or other agreement between parties; provided, however, that in cases in which this title imposes a greater restriction upon the erection, construction, establishment, moving, alteration or enlargement of building or the use of any such building or premises in the several districts or any of them, than is imposed or required by such existing provisions of law or ordinance or by such case the provisions of this title shall control.