In the interpretation and application of the provisions of this chapter, they shall be held to be the minimum requirements adopted for the promotion of the public health, safety, comfort, convenience and general welfare. Except where specifically provided to the contrary, it is not intended by this chapter to repeal, abrogate, annul or in any way interfere with any rules, regulations or permits previously adopted or issued or which shall be adopted or issued pursuant to law relating to the use of buildings, structures, shelter or premises, nor is it intended to interfere with or abrogate or annul any easements, covenants or other legal agreements in effect between parties at the time of adoption of this chapter; provided, however, that where this chapter imposes a greater restriction upon the use of a building or lot or requires larger open spaces than are imposed or required by any other statute, ordinance, rule, regulation or permit, the provisions of this chapter shall prevail.