Building Safety Division - Permits - Detached Accessory Structure (Shed) Requirements

- Revised: September 4, 2012 -

The following information is also available in PDF.



Legal Plat of Survey - indicate on the plat where the structure is to be located.  Include the setbacks from the house, side and rear lot lines.  (See attached copy of the Zoning Ordinance requirements). NOTE:  STRUCTURES CANNOT BE PLACED IN A DRAINAGE OR UTILITY EASEMENT WITHOUT APPROVALS FROM ALL INTERESTED PARTIES.           


Illinois licensed architect or structural engineer signed and sealed plans will be required for detached accessory structures (sheds, garages, gazebos, etc.) if any of the following conditions exist:

  • The accessory structure has an eave height of 10-feet or more above grade at any point;
  • The attic is served with fixed stairs;
  • The accessory structure includes a second story;
  • The design reflects concentrated loads or special loads at any point within its construction (column or I-beam installation, pier pads, etc.); or
  • Accessory structure is greater than 600 square feet in floor area for light frame construction or greater than 400 square feet in size for other than light frame construction.  In addition, structures of this size must be constructed on a frost foundation system, as allowed by the 2012 IRC.

Detached accessory structures less than or equal to 200 square feet used as tool or storage sheds, playhouses and similar uses are not required to be designed by a licensed professional, nor are they required to be installed on a foundation system, unless as noted above.  Provide a drawing/picture of the shed.

Detached accessory structures, which are greater than 200 square feet, but less than 600 square feet, shall be placed upon any foundation allowed by the 2012 IRC with the minimum dimensions reflected in the code.  Requests for a building of this size require submittal of detailed construction prints.

4.         Permit Then Goes in for Review:  It is routed through Zoning, Engineering and Building Departments.
5.         Once permit is approved and paid for, verify:

A.         J.U.L.I.E. has been contacted prior to digging (1-800-892-0123 or 811)
B.         No changes have been made from the approved plans prior to installation
C.         Work must commence within 180 days of issuance of permit

6.         INSPECTIONS

Depending on the size of the shed, conditions as noted above, and type of foundation, various inspections are required.  Below is a basic guideline: 

A.        Under 200 square feet without a foundation/piers – final inspection.
            With a foundation or piers – footing and final.
B.        Greater than 200 square feet, but less than 600 square feet – footing, framing, if concealed, and final.
C.        Greater than 600 square feet – footing, framing and final.


(847) 599-7550    


Inspections can be scheduled by calling
the Building Safety Division at 847-599-7550.
A minimum of 24-hours notice is required.
Please have your building permit number ready;
it is required in order to schedule an inspection.