Iron County, UT Zoning Overlays & Bonuses: Density Bonus Law (2026)

The performance subdivision option is only available in the R-1/2 residential zoning district and only with approval of the appropriate land use authority under Iron County Code § 16.23.020. To qualify, the tract must contain at least twenty acres of contiguous land, and a phased project must plan each phase at least ten acres, per § 16.23.030(B)-(C). Iron County ties the number of lots directly to a density-bonus ladder set out in § 16.23.030(A): Level A allows two units per acre with no open-space set-aside, while each step up to Level E requires progressively more dedicated open space and more scored performance points, topping out at six units per acre with twenty percent open space and twenty performance points at Level E.

The zoning administrator interprets and scores the qualifying values, subject to approval by the land use authority under § 16.23.040(D). Performance subdivisions must also be served by central water and central sewer and sit within a county Tier II or Tier III area, and the property adjacent to the development cannot be adversely affected, with the land use authority able to require lower-intensity uses along the project boundary. Because a performance subdivision is processed alongside the standard preliminary and final subdivision application requirements of Chapters 16.12 and 16.16, the density bonus is confirmed only after the county verifies the open-space and scoring commitments before the plat is recorded.