Chicago RS1 / RS2 / RS3
low-density residential standards.
Chicago's RS districts regulate detached houses by minimum lot area, floor area ratio, side and rear setbacks, and a 30-foot building height.
Plain English
RS1, RS2, and RS3 are Chicago's detached-house districts. They differ mainly in minimum lot area and floor area ratio.
Front setbacks are context-sensitive: the building must match the average front yard of the nearest lots, not a single citywide number.
Rear setbacks for detached houses are 28% of lot depth or 50 feet, whichever is less.
Numbers Pre-Flight checks
| Field | Value | Source |
|---|---|---|
| RS1 lot area / FAR / height | 6,250 sq ft / 0.50 / 30 ft | Sec. 17-2-0301/0304/0311 |
| RS2 lot area / FAR / height | 5,000 sq ft / 0.65 / 30 ft | Sec. 17-2-0301/0304/0311 |
| RS3 lot area / FAR / height | 2,500 sq ft / 0.90 / 30 ft | Sec. 17-2-0301/0304/0311 |
| RS1 side yards | 30% of lot width combined; neither side less than 5 ft or 10% of lot width | Sec. 17-2-0309 |
| RS2 side yards | 30% of lot width combined; neither side less than 4 ft or 10% of lot width | Sec. 17-2-0309 |
| RS3 side yards | 20% of lot width combined; neither side less than 2 ft or 8% of lot width | Sec. 17-2-0309 |
| Rear setback — detached house | 28% of lot depth or 50 ft, whichever is less | Sec. 17-2-0306 |
| Front setback — RS | Average front yard of nearest 2 lots on either side, excluding the least-depth lot | Sec. 17-2-0305 |
Official source
City of Chicago Zoning Ordinance · Chapter 17-2, Residential DistrictsEffective / last checked: Current through June 17, 2026
These pages explain what Pre-Flight checks. Always confirm the adopted text on the city's official site.
Pre-Flight is not a permit, not legal advice, and not a substitute for a licensed design professional or the authority having jurisdiction. The city still decides.