Elgin, IL Building Setbacks & Zoning: Setback Rules (2026)

Elgin created its Residence Conservation districts to conserve mature neighborhoods that developed under significantly different regulations than the current rules for new residential development (§ 19.20.050). RC1 covers neighborhoods that developed predominantly after 1962 with single-family detached dwellings (§ 19.20.105). No new RC1 district can be mapped unless the property adjoins an existing RC1 district along the entire length of at least two of its sides (§ 19.20.125), so the RC1 footprint stays tied to the neighborhoods already mapped.

Section 19.20.135(E) sets four building setback minimums for an RC1 zoning lot. The street setback is 25 linear feet from a street lot line. The side setback is 6 linear feet from a side lot line, and the combined width of the side setbacks cannot be less than 14 linear feet, so a house that sits 6 feet from one side lot line has to leave at least 8 feet on the other side. The interior setback is 6 linear feet from an interior lot line. The rear setback is 30 linear feet from a rear lot line.

The setbacks work together with the other site design standards in the same section. RC1 requires 7,500 square feet of zoning lot area per dwelling unit and a lot width of at least 60 linear feet. A lot at exactly those minimums works out to 125 feet deep, which after the 25-foot street setback and the 30-foot rear setback leaves 70 feet of buildable depth, and after the 14-foot combined side setback leaves 46 feet of buildable width.

Setbacks are not the only cap on how large a house can be. Maximum residential floor area for a new single-family detached dwelling is [(ZLA minus 7,500) x 0.20] + 3,000 square feet, where ZLA is zoning lot area in square feet, and for an addition to an existing dwelling it is [(ZLA minus 7,500) x 0.14] + 2,250. Building coverage for a new dwelling is [(ZLA minus 7,500) x 0.1711] + 3,042 square feet, and for an addition it is [(ZLA minus 7,500) x 0.12608] + 2,480.

Accessory buildings, yards and measurement rules are routed elsewhere. Subsection F sends accessory structures and buildings to section 19.12.500, subsection D sends the general setback rules to section 19.12.400, and subsection G sends the street, side and rear yards created by a setback to section 19.12.600. The four RC1 numbers above are the main-building minimums and do not answer the question for a garage or shed.