Residential Hillside Development

The Residential Hillside (RHS) Ordinance regulates single family residential development in the hillside zones in a manner that preserves the natural setting of the hillsides. The ordinance incorporates performance standards and specific regulations to ensure that the utilization of land for residential uses is balanced with the need to conserve natural resources and protect life and property from natural hazards.

Development that meets the regulations of the RHS ordinance may be permitted through the building permit process. However, in some cases, if an exception to any of the regulations is required to develop the property, a public hearing with the Planning Commission may be necessary. For projects that need a public hearing, please fill out the application form(PDF, 409KB) and pay the fees online or at the Planning Counter.

Development in the RHS zone requires several studies including, but not limited, to arborist reports and geotechnical reports prior to project approval. These reports are peer reviewed by the City's consultants.

RHS Development Standards
Maximum Allowable Floor Area

The calculation of the maximum allowable floor area in the RHS zone is dependent on the lot area and the average slope of the net lot area. The size of all development on property zoned RHS may not exceed 6,500 sq. ft. regardless of the lot area and average slope of the property.

Maximum allowable floor area is the lesser of:

  • 6,500 sq. ft., or
  • 4,500 square feet plus 59.59 square feet for every 1,000 square feet over 10,000 square feet of net lot area times the Slope Adjustment Factor. (4,500 + 59.59 * ((Net lot area - 10,000)/1,000)) x (Slope Adjustment Factor)
Example Calculation

Gross Lot Area: 90,000 sq. ft.
Creek Easement: 12,500 sq. ft.
Driveway Easement: 2,500 sq. ft.

Net Lot Area = Gross Lot Area - Creek Easement - Driveway Easement
(90,000 sq. ft. - 12,500 sq. ft. - 2,500 sq. ft. = 75,000 sq. ft.)

Average Slope of Net Lot Area
The average slope must be calculated by a civil engineer.

20% (0.2)

Slope Adjustment Factor = (1 - (1.5 x (Average Slope of Net Lot Area - 0.1)))
On lots with slopes of over 10%, the allowable floor area is reduced by 1.5% for each percent of slope over 10%.

(1 - (1.5 x (0.2 - 0.1))) = 0.85

Maximum allowable floor area is the lesser of:

  • 6,500 sq. ft., or
  • (4,500 + 59.59 * ((Net lot area - 10,000)/1,000)) x (Slope Adjustment Factor)
      • = (4,500 + (59.59 x ((75,000 - 10,000)/1,000))) x 0.85
      = (4,500 + (59.59 x 74)) x 0.85
      = 8,909.66 x 0.85 = 7,573.21 sq. ft.

Therefore, Maximum Allowable Floor Area is limited to: 6,500 sq. ft.

Setbacks
Lots With Slopes ≤20%
Minimum Front Yard Setback Minimum Rear Yard Setback Minimum Interior Side Setback Minimum Street Side Setback

First Story - 20'

Second Story - 25'

Third Story - 25'

First Story - 20'

Second Story - 25'

Third Story - 25'

First Story - 10'

Second Story - 15'

Third Story - 20'

First Story - 15'

Second Story - 15'

Third Story - 20'
Lots With Slopes >20%
Minimum Front Yard Setback Minimum Rear Yard Setback Minimum Interior Side Setback Minimum Street Side Setback

First Story - 10'

Second Story - 25'

Third Story - 25'

First Story - 20'

Second Story - 25'

Third Story - 25'

First Story - 10'

Second Story - 15'

Third Story - 20'

First Story - 15'

Second Story - 15'

Third Story - 20'
Second Story Decks and Balconies
Minimum Front Yard Setback Minimum Rear Yard Setback Minimum Interior Side Setback Minimum Street Side Setback

Second Story - 17'

Third Story - 17'

Second Story - 20'

Third Story - 20'

Second Story - 15'

Third Story - 15'

Second Story - 15'

Third Story - 15'
Maximum Building Height

Maximum building height for structures in the RHS zoning district is 30' measured from natural grade.

Other Regulations

The RHS ordinance also regulates subdivisions, grading, driveways, accessory structures, fences, outdoor lighting and color scheme. Please read carefully and contact the Planning Division with any questions.

Fences - Fence requirements are different in the RHS zones than in other residential areas.

Driveway gates - Gates may be used to control access to private roads and driveways in the RHS zones as long as the Director of Community Development approves of the design.

Back to top