McLean County, IL Building Setbacks & Zoning: Structure Height Limits (2026)

The R-1 Single-Family Residential District's height regulations sit at § 350-36E. Subsection (1) caps a principal structure at not more than 2 1/2 stories or 35 feet, whichever is less, meaning both the story count and the foot measurement apply and the lower of the two governs. Subsection (2) separately limits an accessory structure's side wall to 12 feet in height unless the code specifies otherwise elsewhere, covering detached garages, sheds, and similar outbuildings on an R-1 lot. Certain roof-level features are carved out of these limits entirely: § 350-44 exempts chimneys, cooling towers, elevator head houses, fire towers, grain elevators, monuments, stacks, stage towers or scenery lofts, tanks, water towers, ornamental towers, spires, church steeples, and other mechanical appurtenances placed above the roof and not intended for human occupancy from the district's height limitations.

The same 35-foot ceiling recurs for the M-1 Restricted Manufacturing and M-2 General Manufacturing Districts at § 350-39E and § 350-40E, so 35 feet functions as the county's general non-farm structure height, while § 350-35H(1) leaves agriculture and farm structures unrestricted in height and caps other agriculture-district uses at 150 feet. Because this is the county zoning code, the R-1 height cap governs only unincorporated land; homes inside Bloomington or Normal follow those cities' separate building height rules.