SECTION 1. Notwithstanding any general or special law to the contrary, upon approval of the town of Truro’s affordable accessory dwelling by-law by the attorney general, any affordable accessory dwelling unit rented under the by-law that is subject to an affordable housing deed restriction shall be exempt from taxation under chapter 59 of the General Laws.

SECTION 2. An exemption under section 1 shall be equal to the real estate tax otherwise owed on the property, based on the assessed value of the entire property, including any accessory structures, multiplied by the square feet of the living space of all accessory structures on the property that are restricted to occupancy by low- or moderate-income households, divided by the total square feet of all structures on the property. For a property with a single affordable accessory dwelling unit, the exemption allowed shall not exceed 50 per cent of the tax otherwise owed. For purposes of determining the assessed value of the entire property, if by income approach to value, such assessment shall assume that all housing units are rented at fair market value.

SECTION 3. The date of determination as the qualifying factors required by this act shall be September 1 of each year.

SECTION 4. The following question shall be placed upon the official ballot and submitted to the voters of the town of Truro at the next annual or special town election: “Shall an act passed by the general court in the year 2011 entitled ‘An act authorizing property tax exemptions for rental properties in the town of Truro restricted as affordable housing’ be accepted?” If a majority of the votes cast in answer to the question is in the affirmative, this act shall take effect, but not otherwise.