The purpose of the F-20 zone is to provide recreational and residential opportunities for property owners within areas of hillside and steep slopes in the city while providing preservation of the natural landscape of hillsides.

There are no permitted uses in the F-20 zone.

Conditional uses in the F-20 zone are as follows:

1. Single family detached dwellings;
2. Planned unit development;
3. Private parks and recreational grounds;
4. Public and quasi-public use;
5. Radio and/or television tower;
6. Temporary structures, as allowed by the applicable accessory regulations in chapter 19.76, “Supplementary and Qualifying Regulations”;
7. Utility stations and lines, as allowed by the applicable accessory regulations in Chapter 19.76, “Supplementary and Qualifying Regulations”; and
8. Wireless telecommunication towers, subject to stealth measures.

1. Health department approval required. Prior to issuance of a conditional use permit or site plan approval for all uses in the F-20 zone, regardless of size or number of units, the applicant shall receive the written approval of the health department certifying that all water quality and health requirements have been satisfied and that the proposed construction will not damage the natural watershed.
2. Developments of more than nine lots/units. Developments of more than nine lots or units shall receive the written approval of the state Department of Environmental Quality certifying that the culinary water system and the sewerage system meet all state water quality and health requirements. All approvals shall be in accordance with the regulations of the state Department of Environmental Quality relating to culinary water supply and wastewater disposal.
3. Applicable state regulations and standards. The applicable state regulations for individual wastewater disposal systems can be found in the Utah Administrative Code, as amended from time to time. The applicable state regulations for culinary water supply can be found in Utah Administrative Code, as amended from time to time.
4. Subsequent changes in site plan. If after health department or state Department of Environmental Quality review and action pursuant to this section, a site plan is modified such that the original limits of disturbance change, the applicant must submit the modified site plan to the appropriate health agency for retesting and a new determination whether all state wastewater and culinary water standards have been met. Evidence of such retesting must be submitted prior to final approval of the site plan.

The minimum lot size for each single-family dwelling, and any other use, in the F-20 zone is 20 acres.

The minimum lot width in the F-20 zone is 350 feet.

Because of the unique nature of development and general concern for preservation of hillsides, individual setbacks for each lot developed in the F-20 zone will be evaluated and determined on a case-by-case basis by the director. If the director wishes, in certain cases he may refer the matter to the planning commission for decision. All setbacks in the F-20 zone shall be subject to the provisions of Chapter 19.72, “Sensitive Lands.”

1. For uses where the slope of the original ground surface is greater than 15%, or if a slope stability hazard is present on site, the maximum structure height shall be 30 feet.
2. All other properties shall maintain a maximum structure height of 35 feet.
3. For accessory buildings, heights will be determined on a case by case basis, subject to the foregoing maximums.

The maximum lot coverage for the F-20 zone is two percent, which includes all structures. For those portions of properties also located in the Sensitive Lands Overlay Zone, all impervious surfaces shall also be included in the percentage calculation.

Disturbance in the F-20 zone shall be limited to 43,560 square feet of each lot. The remaining property shall be left in its natural vegetative state. In no case shall the limits of disturbance be inside a watershed boundary.

Removal of trees or natural vegetation shall not be permitted except in conformance with the standards and requirements set forth in Chapter 19.72, “Sensitive Lands.”