Existing restrictions. The provisions of this chapter shall not annul, or in any way interfere with, existing deed or plat restrictions, easements or other agreements between persons, codes, laws, rules, regulations or permits previously adopted or issued, except those codes or sections which are contrary to, or in conflict with, this chapter. Wherever this chapter imposes greater restrictions upon the use of structures or land, the height or bulk of buildings or requires larger land or building areas, yards or other open spaces than are otherwise required or imposed by deed or plat restrictions or laws, this chapter shall control; other regulations shall control where they impose greater restrictions than this chapter and for that purpose, this chapter shall not annul, modify or impair the provisions of any existing deed or plat restrictions, easements or other agreements.