ADU rules in Kalispell

Since Ord. 1950 (5-4-2026, the city's MLUPA and Land Use Plan Update), § 27.20.082(1) allows a second dwelling unit as a permitted use in any zone where a single-family dwelling is a permitted use, and the unit may be "a separate accessory dwelling unit", the detached backyard form. "Accessory dwelling unit" is listed as a permitted use in the R-1, R-2, R-3, R-5, RA-1, RA-2, H-1, and B-1 through B-4 district use lists, and § 27.20.080 exempts ADUs from the one-principal-structure-per-lot rule in R districts and from conditional use review for multiple structures in RA and H districts. An existing conforming or nonconforming accessory structure (a detached garage, for example) may be converted while keeping its existing setbacks (§ 27.20.082(3)(a)). Before 5-4-2026 the local code allowed a detached second unit by right only in B-1 through B-4 and only by administrative conditional use permit in R-4, R-5, RA-1, RA-2, and H-1 (R-1 got a guest house by CUP); the statewide mandate MCA 76-2-345 overrode those limits from 1-1-2024, and Ord. 1950 brought the printed code into line.

Kalispell reaches attached and internal second units through its duplex taxonomy: § 27.20.082(1) permits the second dwelling unit "as part of a duplex" in any zone where a single-family dwelling is permitted, and § 27.37.010 defines a duplex as two structurally joined dwelling units with separate entrances, which covers additions and basement or internal conversions with their own entrance. Duplexes also appear as a standalone permitted use in every residential district list. The practical result matches MCA 76-2-345(1)(b), under which an ADU "may be attached, detached, or internal"; the label just differs. Note that the ADU-specific conditions of § 27.20.082(2) (1,000 sq ft cap, single-story height limit, no sub-30-day rentals) textually attach to the separate accessory dwelling unit form, while a structurally joined second unit is regulated as a duplex, including the single-family and duplex design standards of § 27.20.110.

§ 27.20.082(2)(b) caps the gross floor area of living space in an ADU at 1,000 square feet, and (2)(a) limits it to a single story no taller than 18 feet unless the unit meets the setbacks required of a principal structure, in which case the district's maximum building height governs. The § 27.37.010 definition separately requires the primary single-family dwelling to be "of greater square footage" than the ADU, so the unit can never match or exceed the main house. An attached second unit taken as a duplex has no 1,000 sq ft cap. While Kalispell zoned under Title 76 ch. 2 pt. 3, MCA 76-2-345(1)(c) set a floor formula (not more than 75% of the primary dwelling's gross floor area or 1,000 sq ft, whichever is less); the city's flat 1,000 sq ft cap is at least as permissive, which 76-2-345(8) allows, and since the 5-4-2026 transition to the Montana Land Use Planning Act the local cap is the operative one.

Neither § 27.20.082 nor any other provision of the zoning ordinance requires the owner to live in either unit; a full-text scan of the codified ordinance finds no owner-occupancy or primary-residence condition on ADUs, and the pre-2026 version had none either. While Kalispell zoned under Title 76 ch. 2 pt. 3, MCA 76-2-345(2)(c) affirmatively barred requiring owner occupancy of either the house or the ADU. Under the Montana Land Use Planning Act, which Kalispell adopted into its zoning on 5-4-2026, the ADU housing strategy at MCA 76-25-302(1)(e) would have let the city condition ADUs on the lot being "occupied as a primary residence", but Kalispell imposed no such condition.

The residential row of the § 27.24.050(7) parking table, rewritten by Ord. 1950 (5-4-2026), reads: single-family residences, accessory single-family, duplex, and multifamily units under 1,200 square feet require no parking, and units over 1,200 square feet require 1 space per unit. Because ADU living space is capped at 1,000 square feet, a Kalispell ADU never triggers a parking requirement (deed-restricted affordable housing is also exempt). This matches MCA 76-2-345(2)(a), which barred ADU parking mandates while the city zoned under Title 76 ch. 2 pt. 3, and anticipates HB 492 (2025), which from 10-1-2026 bars cities over 5,000 from requiring parking for non-multifamily units under 1,200 sq ft. One wrinkle: for parking calculations, gross floor area counts basements with 7 ft clearance, code-compliant access, and a hard floor (§ 27.24.050(6)).

Since Ord. 1950 (5-4-2026), § 27.20.082(1) makes the second dwelling unit "a permitted use" wherever a single-family dwelling is permitted: no conditional use permit and no public hearing. Process is ministerial: minor site plan review under § 27.20.120(2) (two sets of working drawings submitted to the planning and building department to show zoning compliance, the same track as any single-family dwelling or duplex) plus a building permit through the city's permit portal. Before 5-4-2026 the printed code required an administrative conditional use permit for a separate ADU in the R-4, R-5, RA-1, RA-2, and H-1 zones; that requirement was void from 1-1-2024 under MCA 76-2-345(5) because the statute's "by right" definition (76-2-345(9)(b)) excludes conditional use permits, and Ord. 1950 removed it from the text.

§ 27.20.082(2)(c) states flatly that rental periods of less than 30 days are not permitted for the accessory dwelling unit, so an ADU can be a long-term rental but never a short-term one. Other dwellings can seek short-term rental approval under § 27.20.095, which requires an administrative conditional use permit with annual renewal, a life-safety inspection, a State of Montana public accommodation license through the Flathead City-County Health Department, and caps short-term rentals at 2% of residences across all R and RA zones citywide; the categorical ADU bar means an ADU cannot use that path. This local STR authority survives the statewide ADU laws, since MCA 76-2-345(3) expressly preserves municipal regulation of short-term rentals as defined in 15-68-101. The ordinance says nothing about selling an ADU separately from the main house.