Aurora Setbacks & Height Limits — Residential Zones

Fact-checked against Aurora's current Unified Development Ordinance on September 20, 2026.

Aurora's residential dimensional standards are in Section 146-4.2 of the Unified Development Ordinance (UDO). A major point that the previous version missed is that Aurora divides the city into Subareas A, B, and C, and some standards differ by subarea.

Current Base Residential Standards

For the principal residential districts, Tables 4.2-1 and 4.2-2 provide these base standards:

These values are the general residential-district standards. They do not replace the UDO's more specific rules for street-side setbacks, affordable-housing height provisions, special development options, or use-specific standards.

The previous page stated that R-1 had a 35-ft height limit and R-3 had a 40-ft limit. The current UDO table instead lists 38 ft for R-1 and R-2, 45 ft for R-3, and 65 ft for R-4.

Street-Side Setbacks Are Different

A corner or street-side lot should not use the interior-side number by default. Table 4.2-1 and Table 4.2-2 include separate side setbacks for lots abutting local, collector, and arterial streets.

For example, the general local-street side setback is larger than the 5-ft interior-side setback in the residential districts. The exact street classification therefore matters.

Subarea C and Optional Residential Standards

Subarea C has special development options. Section 146-4.2.3 allows certain R-1 and R-2 land to use Small Residential Lot, Flexible Residential Lot, Green Court, Motor Court, and other specific standards when the applicable conditions are met.

Those optional standards can supersede the ordinary table where the UDO says they apply. A project in Subarea C should therefore be checked against both the base table and Section 146-4.2.3 before dimensions are finalized.

Height Exceptions and Neighborhood Protection

The maximum-height row is not the end of the review. Section 146-4.2.4 contains exceptions and encroachment rules, and neighborhood-protection standards can apply near lower-density residential areas.

Planned developments, mixed-use districts, airport-related controls, and approved site plans can also affect what is permitted on a specific parcel.

Accessory Structures and ADUs

Garages, sheds, accessory dwelling units, and other accessory structures can have different standards from the principal building. Do not use the R-1 or R-2 principal-building table as an automatic accessory-building setback table.

For ADU-specific rules, see the Aurora ADU rules page and confirm the current UDO and any applicable Colorado state requirements.

How to Check a Property

1. Find the parcel's current zoning district and Aurora subarea.
2. Use Table 4.2-1 for Subareas A and B or Table 4.2-2 for Subarea C.
3. Check the street classification before applying a side setback on a corner or street-abutting lot.
4. Review Section 146-4.2.3 for special residential development options.
5. Review Section 146-4.2.4 and neighborhood-protection provisions for exceptions or additional limits.
6. Confirm the result with Aurora Planning & Development Services for site-specific questions.

Official Sources

• Aurora UDO Section 146-4.2.2 — General Dimensional Standards
• City of Aurora — Building & Zoning Code

This guide is informational only. Parcel-specific zoning, subarea, street classification, overlays, and approved plans can change the applicable dimensions. Verify current requirements with the City of Aurora before design, permitting, purchase, or construction decisions.