Mesa Residential Small Lot (RSL) District Setback Requirements
In the City of Mesa, the Residential Small Lot (RSL) Single Dwelling Districts establish front building setbacks ranging from 12 to 15 feet and rear setbacks between 15 and 20 feet. These regulations include specialized requirements for garages, which must be set back 20 feet from the front property line, and specific side yard aggregates to ensure adequate separation between dwellings.
RSL District Setback Standards
The City of Mesa categorizes Residential Small Lot Districts based on their minimum average lot size in thousands of square feet, specifically RSL-4.5, RSL-4.0, RSL-3.0, and RSL-2.5. The following table outlines the minimum yard (setback) requirements for these districts [Table 11-5-3.A.2].
| Standard | RSL-4.5 | RSL-4.0 | RSL-3.0 | RSL-2.5 |
|---|---|---|---|---|
| Front - Building Wall | 15 feet | 15 feet | 15 feet | 12 feet |
| Front - Garage | 20 feet | 20 feet | 20 feet | 20 feet |
| Front - Porch | 10 feet | 10 feet | 10 feet | 7 feet |
| Street Side | 10 feet | 10 feet | 10 feet | 10 feet |
| Interior Side (Minimum each side) | 4.5 feet | 4 feet | 4 feet | 3 feet |
| Interior Side (Minimum aggregate of 2 sides) | 10 feet | 10 feet | 9 feet | 8 feet |
| Rear | 20 feet | 20 feet | 20 feet | 15 feet |
| Garage (Accessed by Alley/Common Drive) | 13 feet* | 13 feet* | 13 feet* | 13 feet* |
*Measured from the construction centerline of the alley or drive [Table 11-5-3.A.2].
Special Setback Regulations in RSL Districts
Zero-Lot-Line Developments
The City of Mesa permits zero-lot-line developments within all RSL districts. Under this provision, a structure may have a zero-foot interior side yard on one side of the lot, provided that the opposite side yard meets the minimum aggregate setback defined in the table above or is at least 10 feet, whichever is greater [Section 11-5-3(A)(3)(c)].
To utilize a zero-side yard, the City of Mesa requires that the abutting property be under the same ownership at the time of construction, or the adjacent owner must sign a written agreement granting consent for the zero setback. Additionally, a maintenance easement must be recorded to provide access for the zero-lot-line structure [Section 11-5-3(A)(3)(c)(ii)].
Adjacency to RS Districts
If a lot in an RSL District is located adjacent to a lot in a standard RS (Residential Single Dwelling) District, the City of Mesa requires the RSL lot to match the minimum interior side yard required by the adjacent RS-zoned lot for that specific shared side [Section 11-5-3(A)(3)(d)].
Paving Limitations
In RSL districts, the City of Mesa limits the amount of paving allowed in street-facing yards. No more than 50% of any required front or street-facing side yard may be covered with a paved surface [Section 11-5-3(A)(3)(e)].
Building Projections into Required Yards
The City of Mesa allows certain residential building elements to project into the required setbacks established for RSL districts:
- Awnings and Eaves: May encroach up to 3 feet into any required yard [Section 11-5-3(B)(2)(A)(ii)].
- Wall Projections: Chimneys, bay windows, or nooks may encroach up to 3 feet into front/rear yards and 2 feet into side yards, provided they do not exceed one-third of the length of the building wall [Section 11-5-3(B)(2)(A)(iii)].
- Staircases: May encroach up to 3 feet into the front yard and 10 feet into the rear yard [Section 11-5-3(B)(2)(A)(iv)].
- Porches and Patios: Attached open porches or patios may encroach up to 10 feet into a required rear yard [Section 11-5-3(B)(2)(A)(v)].
Sections Cited
- Section 11-3-1: Districts Established
- Section 11-5-1: General Purpose of Residential Districts
- Table 11-5-3.A.2: Development Standards - RSL Residential Small Lot Single Dwelling Districts
- Section 11-5-3: Development Standards for the RS and RSL District