Bathroom remodeling in Chicago, IL

Plumbing inside Chicago buildings is governed by Chapter 18 29 of the Municipal Code, still based on the 2001 Chicago Plumbing Code with amendments. The Department of Buildings notes that the Illinois Plumbing Code method for counting occupants and minimum fixtures does not apply in the city.

The biggest recent change came in October 2021. After a four year pilot with about 3,000 participants, City Council allowed PVC drain and vent pipe in residential buildings up to 60 feet tall, including the building sewer. It became mandatory for permit applications started on or after March 1, 2022. For a bungalow or a two flat, that means new drain and vent lines inside the house can be PVC.

The city requires a licensed and bonded plumbing contractor for most plumbing work. There is one exception. The owner, occupant or lessee of a detached single family house may do the plumbing in that house personally, with a permit and inspection. They cannot hire an unlicensed helper to do it for them.

That exception does not reach two flats or greystone apartments. If your bathroom is in a two or three unit building, a licensed plumbing contractor has to be on the permit.

Replacing an existing toilet, tub, sink or water heater, or replacing old supply and drain piping, fits the Express Permit Program under Plumbing Work. Fixtures must meet the Chicago Plumbing Code's water efficiency rules or the job is not eligible.

Adding a bathroom is an Interior Alteration. The Express route lets you add up to 5 water supply fixture units of demand, and the city's own example puts a new private bathroom at 4. So one added bathroom fits. A bathroom plus a laundry does not. If the new room means moving walls, an Illinois licensed architect or structural engineer draws it.

When you add fixtures the city also expects the size of your existing water service to be checked against the new demand. The Chicago Bungalow Association's design schemes flag that an added bathroom will most likely need a larger water service if the main was never replaced.

Where a two flat has one bathroom above the other on a shared riser, replacing that riser inside its existing chase can go through the Express route. The application needs a plumbing contractor's drawing of the whole riser, with pipe sizes and materials.

Getting to a second floor drain often means opening the first floor ceiling. In a two flat that ceiling is part of the floor between two dwelling units, and the Chicago Building Code requires a fire resistance rating where a floor separates units. We close it back up to that standard, not just with whatever patch is quickest.

Work in both units at once, or in a shared stair hall, needs drawings from a licensed architect or structural engineer even on the Express route, and the area of work there is capped at 500 square feet.