Compare ADU rules across North Dakota

Dickinson allows one ADU per owner-occupied single-family lot, detached units included, by right in the AG Agricultural, RR Rural Residential (lots of two acres or more), R-2, R-3 and MH districts. ADUs are not allowed in R-1 Low-Density Residential, the city's main single-family district, or in mobile home parks. The R-1 exclusion was deliberate: the Planning and Zoning Commission recommended Ord. 1706 on 10-21-2020 only 'excluding R1 zoning' after residents objected, and the City Commission adopted it on that condition on 11-17-2020. A detached ADU may not sit in the front yard, must be smaller than the house's footprint (attached garage excluded), may cover no more than 10 percent of the lot, and must match the house's residential appearance. No detached ADU is available in the commercial districts, where 62-474(b) allows only attached or internal units.

Ordinance read October 2026

An ADU may be inside the house (a basement or other internal unit) or attached to the house or to a detached accessory structure, in the same districts as detached units: AG, RR on lots of two acres or more, R-2, R-3 and MH, never R-1 and never in a mobile home park. Separately, 62-474(b) allows attached or internal ADUs in the LC, CC and GC commercial districts (not LI or GI) through administrative Planning Department approval; these are 300 to 700 sq ft, capped at two occupants, held under a temporary certificate of occupancy renewed every 12 months, and defined as an apartment for temporary use by an employee of the business. The West Villard and Downtown overlay districts also list ADUs among the uses allowed in single-family structures on commercially zoned lots.

Ordinance read October 2026

Fargo has no ADU use. This value describes the duplex route: a house can become a duplex (two primary units in one structure) by right in SR-3, SR-4, SR-5, MR-1, MR-2, MR-3, UMU, NO, NC, MHP and DMU, and by conditional use in GO, LC and GC. Duplexes are not allowed in AG, SR-0, SR-1 or SR-2. The lot must also meet the district density cap for two units. Under SR-3's 8.7 units per acre, that works out to about 10,000 sq ft of lot for a duplex, so many SR-3 lots are too small. SR-4 (12.1 units per acre) needs about 7,200 sq ft and SR-5 (14.5) about 6,000 sq ft. Under the Dwelling Unit definition, a second kitchen makes the building a multi-dwelling structure unless the extra cooking facilities are 'clearly accessory', so an in-law suite with a kitchen counts as a second unit.

Ordinance read October 2026

Grand Forks's Land Development Code (City Code Chapter XVIII) has no accessory dwelling unit use: quoted searches of the whole city code for 'accessory dwelling', 'accessory apartment', 'garage apartment', 'second dwelling', 'accessory living' and 'granny' return zero hits, and the city's own October 2025 Middle Housing Code Analysis says 'ADUs are not permitted in any residential zones.' The only detached accessory living unit the code allows is a guest house, defined in Sec. 18-0204 as 'an adjunct living unit, with sleeping area(s) and a bathroom, with or without kitchen facilities', and Table 18-0206(3) lists it as a conditional use (C/C) only in the A-1 agricultural preservation and A-2 agricultural urban reserve districts. Under Sec. 18-0206(3)(N) it needs a parcel of at least 5 acres, one per parcel, an owner living on the property, and a recorded covenant against separate sale, lease or rental. In R-1 through R-4, U-D and the other residential districts a second detached dwelling is not a listed use, and the Board of Zoning Adjustment may not grant use variances (Sec. 18-0602(1)).

Ordinance read October 2026

There is no attached or internal ADU category either, but a second unit inside or attached to a house is lawful in some districts as a two-family dwelling, defined in Sec. 18-0204 as 'A dwelling designed for and occupied by not more than two (2) families and having an unpierced common wall, roof, or floor.' Two-family dwellings are permitted by right in R-2 (Sec. 18-0209(2)(B)), and through R-2's use list in R-3 and R-4 (Secs. 18-0210(2)(A), 18-0211(2)(A)) and the U-D university district (Sec. 18-0221(2)(A)), on lots of at least 7,000 sq ft and 50 ft wide (6,000 sq ft suffices for a single-family home). R-1, which covers over 70 percent of the city's residentially zoned land, permits only single-family detached dwellings (Sec. 18-0208(2)(A)); its one multifamily route is a conditional use limited to existing historic structures, and Sec. 18-0208(11)(A)3 says 'Conversion of existing single family structures to multifamily is prohibited.' Even where allowed, the result is a duplex of two co-equal units, not a subordinate accessory unit.

Ordinance read October 2026

It depends on the route. The guest house conditional use requires that 'The owner must reside on the real property and said property must be the owner's primary place of residence' (Sec. 18-0206(3)(N)3), and that the guest house 'shall not be used in a fashion as to constitute a second primary residential use on the property' ((N)4); the permit is indefinite but revocable for any violation ((N)1 and (N)10). The two-family dwelling route in R-2, R-3, R-4 and U-D carries no residency condition (Sec. 18-0209(2)(B) lists it as a plain permitted use), so both units of a duplex may be rented. North Dakota has no statute imposing or preempting ADU owner occupancy, and the Legislative Assembly does not meet again until January 2027.

Ordinance read October 2026

It depends on the route and district. A two-family dwelling in R-2, R-3, R-4 or U-D is a permitted use, so a conversion or new duplex needs only a building permit reviewed by the zoning administrator (Secs. 18-0501, 18-0506(1)), with no hearing. A guest house in A-1 or A-2 is a conditional use: application to the Planning and Zoning Commission, at least one public hearing, a recommendation, and a decision by the City Council (Sec. 18-0703(1)-(2)), with the conditions of Sec. 18-0206(3)(N) attached. In R-1 there is no permit path at all: a second unit is neither permitted nor conditional, the Board of Zoning Adjustment may not vary uses (Sec. 18-0602(1)), and only a rezoning or a PUD (Sec. 18-0223) adopted by City Council ordinance could allow one.

Ordinance read October 2026

A second unit inside or attached to the house is clearly allowed by right in R1-A, R2, R2-A and R3, where Table 6.1 permits a 'Two-Family Dwelling' (a building containing two dwelling units on one lot, with separate entrances); there the unit is built as a duplex conversion or addition, and the district's minimum lot area for 2-4 family dwellings is 8,000 sq ft. In R1, the main single-family district, and in POC a two-family dwelling is not permitted, and the text does not settle whether the undefined 'Accessory Dwellings' use covers a unit within or attached to the house: its only supplemental reference is the accessory-building section, which points to a separate structure. R1 owners should get a written determination from the zoning administrator before designing an internal or attached unit.

Ordinance read October 2026

There is no attached or internal ADU either, but a second unit inside or added onto a house is possible where a two-family dwelling ('a building designed or used exclusively for occupancy by two families', Sec. 46-1) is allowed. Two-family dwellings are permitted by right in R-2 (Sec. 46-145(b)(2)), R-3 (which takes every R-2 use, Sec. 46-146(b)(1)) and RB-4 (any R-3 use, Sec. 46-166(b)(1)); they are special exceptions decided by the board of adjustment in R-1b and R-1c (Secs. 46-143(c)(4), 46-144(c)(3)) and by the planning commission in the ETZ-1 extraterritorial district (Sec. 46-213(c)(6)), while R-1a and the agricultural district allow no second unit at all. Lot area is the usual gate: 10,000 sq ft for a duplex in R-2 (down to 6,000 sq ft by special exception on plats approved before May 15, 1947), 8,400 sq ft in R-3 (6,000 sq ft plus 2,400 sq ft and 20 ft of frontage for the added unit), and the per-family minimums of 12,000 sq ft in R-1b and 5,000 sq ft in R-1c counted for each family. Even where allowed, the result is a duplex of two co-equal units, not a subordinate accessory unit.

Ordinance read October 2026

It depends on the district. In R-2, R-3 and RB-4 a two-family dwelling is a permitted use, so the zoning officer issues a zoning and use registration permit (Secs. 46-50, 46-51) alongside the building permit, with no hearing. In R-1b and R-1c (and in B-2) it is a special exception: such permits 'shall be issued only upon order by the board of adjustment' (Sec. 46-27(a)), which weighs neighboring property values, traffic, sewer and water capacity and community need and may attach conditions (Sec. 46-73(3)); the planning commission sits as the board in the extraterritorial zone (Secs. 46-75, 46-213(c)). In R-1a and the agricultural district there is no route short of a rezoning, because the board 'does not possess the power to permit a use not generally or by special exception permitted in the district involved' (Sec. 46-73(6)). Converting an existing building is less clear: Sec. 46-308 says the board 'may recommend a variance to permit the conversion of any building into a two-family or multiple-family dwelling in any permissible residential district', and R-3 lists such conversions as a special exception (Sec. 46-146(c)(2)), so a house conversion even in R-2 or R-3 may be sent to the board.

Ordinance read October 2026

West Fargo's zoning code (Title IV) has no accessory dwelling unit use: the phrase never appears, and a detached accessory building may not be lived in. Accessory buildings in residential districts are capped at 1,000 sq ft and one story or 15 ft (Sec. 4-442), and Sec. 12-0714 (Ord. 1256, 2025) makes it a class B misdemeanor to reside or sleep in a building not designed or designated for residential occupancy. The only detached route is a second principal single-family house: Sec. 4-444 lets more than one principal structure stand on a lot 'in any district' if each meets the yard and other requirements 'as though it were on an individual lot', so the lot must be big enough to be two conforming lots (6,000 sq ft and 60 ft of width each in R-1A, 5,000 sq ft and 50 ft in R-1, for example), and each house needs street frontage and must meet the single-family dwelling standards (at least 900 sq ft on the main floor for a one-story house). In the R-R district the 1-unit-per-3-acres density cap applies, and city staff relied on it in 2024 to refuse a second house on an occupied lot.

Ordinance read October 2026

There is no attached or internal ADU either, but adding a second unit inside or onto a house is lawful where a two-family dwelling is a permitted use: R-1 (One and Two-Family), R-1S, R-1SM, R-2 and R-3 (Secs. 4-423.2, 4-423-A.2, 4-423-B.2, 4-424.2, 4-425.2), plus the downtown DMU district, where all but three listed uses are permitted. Title IV defines a two-family dwelling as 'a detached residential building containing two dwelling units', and any separate housekeeping unit with its own cooking and sleeping facilities is a dwelling unit, so a basement or addition apartment turns the house into a duplex of two co-equal units. The lot must meet the two-family minimums: 7,000 sq ft and 70 ft wide in R-1; 6,000 sq ft and 60 ft in R-1S and R-1SM; 6,000 sq ft and 50 ft (lots created before 1970) or 60 ft in R-2 and R-3. In the single-family districts (R-L1A, R-1A, R-1B, R-1E, R-R) and the A district only single-family dwellings are allowed, and a use variance is barred, so a second unit there needs a rezoning or a PUD.

Ordinance read October 2026

There is no attached or internal ADU either, but a second unit inside or attached to a house is lawful in some districts as a two-family dwelling. Section 31 defines a two-family dwelling to include 'a building containing two single-family dwelling units located on the same lot', and a duplex as two units 'separated horizontally or vertically, within a single building on a single lot'. So a basement apartment or addition with its own kitchen makes the house a duplex. Duplexes or two-family dwellings are permitted by right in R-2 (lot of at least 8,000 sq ft, 50 ft wide), R-3 (6,000 sq ft, 50 ft), and the manufactured-home districts R-6 and R-7 (8,000 sq ft, 60 ft). In R-1 a two-family dwelling is only a special permitted use, and A, R-1E, R-1A and R-4 have no two-family route at all.

Ordinance read October 2026

There is no ADU permit, so the process depends on the two-family route and the district. In R-2, R-3, R-6 and R-7 a duplex is a permitted use: the Building Official issues a building permit and a certificate of occupancy (Sections 26.D and 26.E), with no hearing. In R-1 a two-family dwelling is a special permitted use, which means a written application ($250 fee) and a hearing before the Planning and Zoning Commission, which may deny it or attach conditions (Section 27). In A, R-1E, R-1A and R-4 the only route is a rezoning. A detached second dwelling cannot be approved anywhere, because Section 25.B bars living in accessory buildings and the Board of Adjustments may not grant a variance 'to allow a use not permissible' in the district (Section 28.B.2.c).

Ordinance read October 2026