(a)  A city or town council is authorized and empowered to provide by ordinance that no permit for the erection of any building shall be issued unless the building lot abuts a street which has been placed on the official map giving access to the proposed structure, and that before a permit is issued, the street has been certified to be suitably improved, or suitable improvements have been assured by means of a performance guarantee, in accordance with rules and regulations adopted in the same manner as rules and regulations for subdivisions as provided in chapter 23 of this title.

(b)  Where the enforcement of this section would entail practical difficulty or unnecessary hardship, or where the circumstances of the case do not require the structure to be related to a street, the board or council may, in a specific case and after a public hearing for which reasonable notice has been given to all interested parties and at which parties in interest and others have an opportunity to be heard, make reasonable exceptions and issue a permit subject to conditions that will assure adequate access for firefighting equipment, ambulances, and other emergency vehicles necessary for the protection of health and safety and that will protect any future street layout shown on the official map.