The provisions of this chapter shall be interpreted, construed and applied as 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 to impair or interfere with any existing provisions of law or ordinance or any rules, regulations or permits previously adopted or issued or which shall be adopted pursuant to law relating to the use of buildings or premises except as expressly provided herein, nor is it intended by this chapter to interfere with or abrogate or annul any easements, covenants or other agreements between parties; provided, however, that where this chapter imposes a greater restriction upon the height of buildings or the use of buildings or requires larger yards, courts or other spaces than are imposed or required by such existing provisions of the law or ordinance, or by such rules, regulations or permits or by such easements, covenants or agreements, the provisions of this chapter shall control.