ADU rules in Bar Harbor

A detached backyard ADU is allowed by right wherever residential uses are allowed, on any lot where a single-family dwelling is the principal structure. Land Use Ordinance § 125-69BB(2)(c)[2][c] lets an ADU sit in a new or existing structure or inside an existing accessory structure, and the subsection's own definition describes an ADU as located within, attached to or detached from the single-family dwelling. One ADU per lot. The review is a building permit or change of use permit from the Code Enforcement Officer, not a hearing. Bar Harbor adopted these rules at the June 11, 2024 Annual Town Meeting (Article 4) to comply with LD 2003 and LD 1706, replacing the town's older bonus dwelling unit program.

Internal conversions and attached additions are allowed on the same terms as detached units. § 125-69BB(2)(c)[2][c] permits an ADU located within an existing dwelling unit or attached to or sharing a wall with the single-family dwelling. An ADU inside or attached to the house, or in a new structure, has to meet the same dimensional standards as the single-family dwelling itself; one placed in an existing accessory structure only has to meet accessory-structure setbacks. No separate use permit or hearing applies.

Bar Harbor sets a floor but no ceiling. § 125-69BB(2)(c)[2][j] requires at least 190 square feet (deferring to any different minimum the state Technical Building Codes and Standards Board adopts under 10 M.R.S. § 9722), and no square footage cap or percent-of-primary-dwelling cap appears anywhere in Chapter 125. What actually limits an ADU is the district envelope: § 125-69BB(2)(c)[2][f] exempts ADUs from minimum lot size and minimum area per family but requires compliance with all other local dimensional standards, so the district's maximum lot coverage (25% in Village Historic, 35% in several residential districts, up to 90% downtown) and maximum height (commonly 40 feet) govern. 30-A M.R.S. § 4364-B(6) permits a municipality to impose a maximum; Bar Harbor has not.

Nothing in Bar Harbor's ADU rules requires the owner to live on the property, at application or afterward. A full-text search of Chapter 125 turns up no owner-occupancy condition attached to ADUs; the single owner-occupied reference in the chapter belongs to the affordable housing standards at § 125-69R and has nothing to do with ADUs. Note the contrast with the town's short-term rental rules, where a VR-1 registration does require the owner's primary residence on the lot, but ADUs are barred from short-term rental use anyway. Maine's statutory ban on municipal owner-occupancy requirements, 30-A M.R.S. § 4364-B(4)(E), does not reach municipalities until July 1, 2027, so Bar Harbor's silence here is its own policy rather than preemption.

§ 125-69BB(2)(c)[2][i] states flatly that accessory dwelling units are not subject to parking requirements, so no off-street space has to be added for the ADU anywhere in town. This tracks 30-A M.R.S. § 4364-B(4)(C), which has barred ADU-specific parking requirements since the mandate's January 1, 2024 implementation date and is unaffected by the 2025 and 2026 amendments. The single-family dwelling's own parking obligation under § 125-67B(4) is unchanged.

Administrative review. § 125-69BB(2)(c)[1] assigns ADUs to a building permit or a change of use permit from the Code Enforcement Officer, with site plan review reaching them only when subdivision is triggered. No Planning Board hearing, conditional use permit, or variance is involved in the ordinary case. Before a certificate of occupancy the owner must show the ADU is connected to adequate water and wastewater and served by potable water. A separate Shoreland Zone Permit applies to ADUs in shoreland districts, and work in the Design Review Overlay District still goes to the Design Review Board.

An ADU can be rented year-round but never to visitors. § 125-69BB(2)(c)[3] provides that none of the dwelling units expressly permitted under the subsection may be registered or used as short-term rentals, naming both vacation rental-1 and vacation rental-2, so an ADU is shut out of Bar Harbor's registration regime entirely: the two-VR-1-per-tax-ID limit, the town-wide VR-2 cap of 9% of all dwelling units, and the two-night and four-night stay minimums in § 125-69Y are simply unavailable to it. A long-term rental, meaning 30 consecutive days or more for compensation, is allowed, but Chapter 130 requires the owner to register each unit annually with the Code Enforcement Officer; registration is free, expires December 31, and cannot be transferred between owners or properties. There is no primary-residence test and no cap on long-term ADU rentals.