ADU rules in Pocatello

A detached backyard ADU is allowed by right in every residential zoning district, with no hearing. Table 17.03.500 lists Accessory Dwelling Units as an R8 restricted use in RE, RL, RMS, RMM, RH and RCP (and R6,8 in the CG and CC commercial districts), and § 17.03.500.A.2 defines a restricted use as one 'permitted outright only when in compliance with special requirements, exceptions, or restrictions'; note 8 routes the reader to § 17.06.100. Section 17.06.100.C.1 expressly contemplates a unit 'constructed as a separate accessory structure on the same lot as the single-family dwelling', and § 17.06.100.B says accessory dwellings 'are permitted in all residential, commercial, and mixed use zoning districts'. Two real gates apply: only one accessory unit per lot, and the lot must meet 'the minimum lot size of the applicable residential district' (§ 17.06.100.C.2), which Table 17.03.600 sets at 15,000 sq ft in RE, 7,500 in RL, 5,000 in RMS and 4,200 in RMM and RH, so a legally nonconforming undersized lot does not qualify. Despite the sweeping language in § 17.06.100.B, the use table is N (not permitted) for ADUs in the OP, LI and I districts, and § 17.06.100.B itself says the more restrictive standard controls.

An internal or attached ADU is allowed on exactly the same by-right terms and under the same standards as a detached one; Pocatello writes a single rule for both. Section 17.06.100.C.1 defines an accessory residential unit as 'a second dwelling unit either within or added to an existing detached single-family dwelling, or constructed as a separate accessory structure on the same lot', and § 17.01.150 defines DWELLING UNIT, ACCESSORY in matching terms. The host building must be a detached single-family dwelling, so the code gives no ADU right to the owner of a townhome, duplex unit or condominium, and only one accessory unit is permitted per lot regardless of type. The 750 sq ft and one-bedroom caps of § 17.06.100.C.3 bind a basement conversion just as tightly as a new backyard cottage, which is unusually restrictive for internal units.

Section 17.06.100.C.3 is flat and short: 'An accessory residential unit shall not exceed seven hundred fifty (750) square feet in size and shall not have more than one bedroom or sleeping room.' There is no percentage-of-primary alternative, no per-zone variation and no split between internal and detached units; the same 750 sq ft applies in RE as in RH. Height is separately capped by § 17.06.100.C.5 at the lesser of the height of the main structure and the underlying district maximum, which Table 17.03.600 puts at 35 ft in RE, RL, RMS and RMM and 45 ft in RH and RCP. The 750 sq ft figure now sits below the state floor: Idaho Code § 67-6541(2)(d), added by 2026 ch. 265 and effective July 1, 2026, directs covered cities to 'Prohibit limiting the size of an accessory dwelling unit to less than one thousand (1000) square feet or seventy-five percent (75%) of the size of the primary dwelling' by February 1, 2027. Until Pocatello amends Title 17, 750 sq ft is the number a permit will be measured against.

Yes, and it is recorded against the title in perpetuity. Section 17.06.100.C.9 provides that 'A deed restriction shall be recorded requiring that either the primary unit or the accessory unit be owner occupied.' The city's live fill-in form, titled 'Accessory Dwelling Unit Restrictive Covenant' and posted under Legal Documents on the Applications and Forms page, states the restriction the applicant must sign and notarize: the ADU and primary residence 'shall not be sold separately nor shall parcel be subdivided. Additionally, either the primary dwelling or accessory dwelling shall be owner occupied in perpetuity.' The owner may choose which of the two units to live in and may rent the other. This requirement is on a clock: Idaho Code § 67-6541(2)(e) directs covered cities to 'Prohibit an owner-occupancy requirement for the primary dwelling or for the accessory dwelling unit' by February 1, 2027, but the local deed restriction is still codified and still being administered as of this check.

Section 17.06.100.C.4 sets an ADU-specific rule that runs the opposite way from most cities: 'If on street parking is available adjacent to the primary dwelling and off site parking standards are met for the primary dwelling, only one additional off street parking space shall be required for the accessory residential unit. If on street parking is not available for the primary structure, two (2) off street parking spaces shall be provided for the accessory dwelling unit.' Table 17.05.570-1 has no ADU row at all, so § 17.06.100.C.4 is the operative standard; the house itself separately needs 1 to 2 spaces depending on bedroom count. Inside the Original Townsite Overlay, on-street spaces along the frontage may be counted toward up to 50 percent of the off-street requirement (§ 17.04.220.D.4), and the director may administratively adjust any parking count by up to 10 percent (§ 17.05.570.B). Idaho Code § 67-6541(2)(b) forces a change by February 1, 2027, requiring covered cities to 'Prohibit requiring any off-street parking or guest parking for any accessory dwelling unit unless the principal dwelling unit does not have off-street parking or the street is not paved and designed or constructed for on-street parking or unless the principal dwelling unit is within one-fourth (1/4) mile of transit, an employment area, or commercial services.' Read that last clause the way it is written: proximity to transit, jobs or shops preserves the city's power to require parking rather than removing it.

Administrative, with no discretionary hearing. Table 17.03.500 classifies Accessory Dwelling Units as a restricted use, and § 17.03.500.A.2 defines that as 'permitted outright only when in compliance with special requirements, exceptions, or restrictions, in addition to the applicable provisions of this title'; the conditional use category (C) and its hearing-body approval under § 17.02.130 do not apply. Section 17.02.200.C names the applications that need special permitting (subdivisions, rezoning requests, planned unit developments, annexation requests, conditional use permits and variances), and ADUs are not among them; review runs through the staff-level Site Plan Review Committee under § 17.02.500 plus the ordinary building permit. The city's Applications and Forms page lists 'Accessory Dwelling Units' as a land use permit type filed through the eTRAKiT portal, with the recorded deed restriction as the one extra submittal. Idaho Code § 67-6541(3), in force since July 1, 2026, independently requires that conforming ADU projects 'shall be approved administratively and as a matter of right, without the need for discretionary approval', so this is the one field where Pocatello already matched the new state law.

Renting out an ADU long term is ordinary in Pocatello, but only one of the two units can be leased, because § 17.06.100.C.9 requires a recorded deed restriction keeping either the primary or the accessory unit owner occupied. Selling the accessory unit off is not an option either: the city's recorded covenant states the two 'shall not be sold separately nor shall parcel be subdivided', and § 17.06.100.C.10 separately prohibits any 'Subdivision or other lot split into substandard lots'. Short-term use is squarely permitted: Table 17.03.500 lists Short-term Rental as a P permitted use in RE, RL, RMS, RMM, RH and RCP, and § 17.01.150 defines it as 'The rental or lease of any dwelling unit or portion therein for a period of not more than thirty (30) days. See Idaho Code § 67-6539.' Pocatello has no short-term rental licensing chapter anywhere in the code (Titles 3, 5, 8, 9 and 15 were enumerated and contain none) and no STR page on the city website, which is now the only lawful posture: Idaho Code § 67-6539(5), as rewritten by 2026 ch. 22 effective July 1, 2026, provides that 'No county or city shall require a license, fee, permit, certification, or registration to operate a short-term rental.' The ADU owner-occupancy covenant is a zoning condition attached to the accessory unit rather than a rule imposed because of short-term rental use, so it is not swept away by the § 67-6539(2)(a)(i) ban on owner-occupation requirements, but its practical effect is that an absentee investor cannot short-term rent both units.