Accessory Structures in Mount Prospect, IL (2026)
3 verified accessory structures rules for Mount Prospect, Illinois, sourced directly from the municipal code and official government pages.
Verified from official government sources
ADU Rules
The Village of Mount Prospect has no accessory dwelling unit permission. Section 14.312 bans leasing, maintaining or building an unpermitted second housekeeping unit, with limited exceptions such as pre-May 2, 1944 two flats and units with free and unlimited access to the rest of the home. Violators face a minimum mandatory penalty, with each day a separate violation.
Mount Prospect Second Housekeeping Unit and ADU Rules
Heavy RestrictionsMount Prospect Village Code § 14.312
A. Prohibited Acts: ... Except for as provided in subsection B of this section, no person shall: 1. Enter into any lease or rental agreement of any kind or nature or otherwise maintain or permit for living purposes the use of an unpermitted second housekeeping unit. 2. Establish, install or construct an unpermitted second housekeeping unit within the corporate boundaries of the Village. ... ......
Shed & Carport Rules
In the Village of Mount Prospect, a shed in a residential district can be no larger than the smaller of two percent of the lot area or 200 square feet. It sits 3 feet from interior side and rear lot lines on lots 55 feet wide or narrower, and 5 feet on wider lots. It cannot store motor vehicles or serve as office, work or living space.
Mount Prospect Shed Size and Setback Rules
Some RestrictionsMount Prospect Village Code § 14.306
6. Shed Restrictions: A shed shall not be utilized to store motor vehicles or as office, work or living space. The storage of household items, equipment to maintain the property and small recreational equipment is permitted. ... ... B. Restrictions In Residential Districts: 1. Maximum Size: a. A detached private garage may be no larger than six hundred seventy two (672) square feet. b. A shed, ...
Garage Conversions
The Village of Mount Prospect allows an attached single-family garage to become living space only if a new garage of equal or greater size is provided for the same number of vehicles, the old garage door is replaced with matching exterior materials, and the old driveway is removed. Section 14.315 sets the conditions.
Mount Prospect Attached Garage Conversion Rules
Significant RestrictionsMount Prospect Village Code § 14.315
The conversion of a single-family residential attached garage into living space shall be permitted subject to the following conditions and all other applicable regulations within this code: A. A new garage space equal to or greater than the amount to be converted shall be provided. The new garage space shall provide sufficient space to park the same number of vehicles as exists in the garage sp...
Looking for Cook County county-wide rules?
County ordinances apply to unincorporated areas and may supplement Mount Prospect city rules.
Accessory Structures in Cook County →