Accessory Structures in Polk County, IA (2026)
5 county-level rules, plus city-specific rules for 1 city in Polk County, Iowa.
Verified from official government sources
ADU Rules
Unincorporated Polk County allows one ADU per property, up to 1,200 sq ft and no larger than the principal residence. The owner must live on-site, the ADU meets principal-dwelling setbacks, and none is allowed in a FEMA floodplain.
Accessory Dwelling Units in Unincorporated Polk County
Some RestrictionsPolk County Zoning Ordinance, Art. 4, Div. 4, Sec. 2 (Accessory dwelling unit)
A maximum of one (1) accessory dwelling unit may be permitted per property. The gross square footage of the accessory dwelling unit shall not exceed one thousand two hundred (1,200) square feet of gross floor area... Accessory dwelling may not be larger than the existing principal residence.
ADU Owner Occupancy
An accessory dwelling unit in unincorporated Polk County requires the property's legal owner to actually live there. Either the main house or the ADU must be the owner's legal residence, proven by title records and the homestead tax credit, under the county zoning ordinance's ADU standards administered by Public Works Planning and Development.
ADU Owner-Occupancy Rule in Polk County
Some RestrictionsPolk County Zoning Ordinance, Art. 4, Div. 4, Sec. 2(F)(5)
(5) The legal owner of the property shall reside on the property for an accessory dwelling unit to be placed. Either the primary dwelling unit or the ADU shall be ... the legal residence of the owner of the property, as reflected in title records and as evidenced by homestead tax credit. (a) The property owner shall provide a covenant or other form of deed restriction... providing for the ADU t...
ADU Rental Restrictions
Polk County's accessory dwelling unit rules stop an ADU from becoming its own separate property. The zoning ordinance bars selling, leasing, dividing or otherwise segregating an ADU's ownership from the primary dwelling unit unless the parcel can independently meet zoning and subdivision standards, and floodplain and utility rules apply on top of that.
ADU Rental & Sale Restrictions in Polk County
Some RestrictionsPolk County Zoning Ordinance, Art. 4, Div. 4, Sec. 2(F)(9)
(9) No ADU shall be sold, leased, divided or otherwise segregated in ownership from the primary dwelling unit, unless zoning and subdivision standards can be met. (10) No ADU shall be permitted in FEMA mapped floodplain. (11) Density limits shall not apply to accessory dwelling units. ... (14) ADU's are required to meet public water and wastewater requirements. ADU's may connect to an existing ...
Shed & Carport Rules
A shed under 720 sq ft must sit at least 5 feet from side and rear property lines; larger sheds need 10 feet. Sheds must be at least 10 feet from the house, cannot exceed 24 feet in height, and generally cannot go in the front yard.
Shed and Accessory Building Rules, Unincorporated Polk County
Some RestrictionsPolk County Zoning Ordinance, Art. 4, Div. 6, Sec. 1(G) (Residential Accessory Buildings)
If the gross floor area of an accessory building is: (1) Seven hundred twenty (720) square feet or less, it shall be located at least five (5) feet from the side or rear property line; (2) More than seven hundred twenty (720) square feet, it shall be located at least ten (10) feet from the side or rear property line.
Tiny Homes
Unincorporated Polk County bars any standalone tiny home from qualifying as an accessory dwelling unit. The zoning ordinance's ADU rules cap a legal ADU at 1,200 square feet and require it to be built into or attached to the main structure, but a freestanding tiny home, mobile home, travel trailer or RV is flatly excluded from the ADU program.
Tiny Homes Cannot Be ADUs in Polk County
Heavy RestrictionsPolk County Zoning Ordinance, Art. 4, Div. 4, Sec. 2(F)(6)
Accessory dwelling units are permitted subject to the following conditions: (1) A maximum of one (1) accessory dwelling unit may be permitted per property. (2) The gross square footage of the accessory dwelling unit shall not exceed one thousand two hundred (1,200) square feet of gross floor area, exclusive of garage, porch or deck area. Accessory dwelling may not be larger than the existing pr...
Accessory Structures by City in Polk County
1 cities in Polk County have their own accessory structures rules. Each link goes to that city's dedicated page with code citations.
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