SECTION 1. Section 3 of chapter 40A of the General Laws, is hereby amended by adding the following paragraph:-

No charter provision, zoning ordinance, by-law or any rule or regulation, in any city or town shall prohibit, or require a special permit for, permitting or construction by attaching to, constructing within, or constructing upon a single family residence, parcel or lot, that is occupied by the owner, an accessory dwelling unit as defined in section 1A.

SECTION 2. The fifth paragraph of section 5 of said chapter 40A, is hereby amended by striking out clauses (1) and (2) and inserting in place thereof the following 2 clauses:-

(1) an amendment to a zoning ordinance or by-law to allow any of the following as of right: (a) multifamily housing or mixed-use development in an eligible location; or (b) open-space residential development;

(2) an amendment to a zoning ordinance or by-law to allow by special permit: (a) multi-family housing or mixed-use development in an eligible location; (b) an increase in the permissible density of population or intensity of a particular use in a proposed multi-family or mixed use development pursuant to section 9; or (c) a diminution in the amount of parking required for residential or mixed-use development pursuant to section 9;.