Johnson County, IA Parking Rules: Driveway Rules (2026)
Key Facts
- One-way driveway minimum width
- 12 feet
- Two-way driveway minimum width
- 24 feet
- Secondary road access approval
- Required from County Engineer
- Minimum parking stall size
- 9 ft. by 18 ft.
- Applies to
- Unincorporated Johnson County only
Summary
Every property in unincorporated Johnson County that must provide off-street parking, including single-family homes, needs a driveway at least 12 feet wide for one-way access or 24 feet wide for combined two-way ingress and egress, and any access onto a secondary county road needs County Engineer sign-off.
Parking Lot Ingress and Egress. The following standards apply to the ingress and egress point between the lot and the public or private road system. In all cases, accesses onto the secondary road system must be approved by the County Engineer. Separate ingress and egress: Driveways shall be a minimum of twelve (12) feet wide. Two-way ingress and egress: Driveway shall be a minimum of twenty four (24) feet wide.
Official source re-checked September 7, 2026: the cited page had not changed since it was quoted.
Full Breakdown
The UDO's off-street parking chapter applies to "all cases that provision of off-street parking is required," a category that includes single-family homes, which must provide one parking space per dwelling unit. Under the Parking Lot Design Standards, driveways built as a separate ingress and a separate egress point must each be at least 12 feet wide, while a single driveway serving two-way traffic must be at least 24 feet wide. Any access point connecting a lot to the secondary road system requires approval from the County Engineer before it can be built, regardless of width.
The same section sets the minimum parking stall at 9 feet by 18 feet and requires parking lots to avoid dead-end aisles unless they end in a hammerhead or cul-de-sac turnaround at least 50 feet across. Where the driveway is part of a formal commercial or multi-family Site Plan, the interior travel surface must additionally meet a minimum dust-free or crushed-rock surface standard tied to the site's review tier. Because this chapter sits in the Unified Development Ordinance, it binds only unincorporated Johnson County; a driveway inside Iowa City, Coralville, or North Liberty is instead governed by that city's own subdivision or zoning code.
Violations & Fines
Building or widening a driveway or access point that does not meet the minimum width, or connecting to a secondary road without County Engineer approval, is enforceable as a County Infraction under Chapter 8:8. A first offense carries a civil penalty of up to $750, a repeat offense up to $1,000, and the Zoning Administrator may also withhold or revoke a related site or building permit until the access is corrected.
Frequently Asked Questions
How wide does my driveway have to be in unincorporated Johnson County?
Do I need approval to add a new driveway onto a county road?
Does this rule apply if I live in Iowa City or Coralville?
Sources & Official References
Other rules in Johnson County
Compare Johnson County to another location·View the Iowa parking rules overview
See something wrong?
Help us keep this page accurate. If you notice an error or outdated information, let us know.