Portland City Code ch. 6 (Buildings and Building Regulations) § 6-237

change the housing unit or do not require repairs substantially different from those that would be required to bring the rental unit into compliance with the Maine Warranty of Habitability Act or local building or housing codes applicable

Portland City Code ch. 6 (Buildings and Building Regulations) § 6-133

this section, “recreational shelter” means any building, structure, vehicle, trailer, or other enclosure used or intended for human habitation that does not meet the standards set forth in Articles II through IV of this Chapter, or the State of Maine