Chicago Rear Addition (RS3 Zoning)

2 Replies

Hello - I am seeking some input on building a fairly simple rear addition on a prospective SFH and long-term hold. I want to ensure I'm not overlooking anything prior to making an offer. Most likely it would be an expanded living room + 1 bedroom & no plumbing involved.

The existing house is RS-3 Zoned on a standard 25' x 125' lot and the home's current length is about 50' offering about ~800 sq/ft on the main level.  That does not include the attic or basement. My understanding is that the Rear Setback = 50ft or 28% (35 ft) // Rear Yard Min = 225 sq (25' x 9 ').

Is there anything else I should know about this kind of project? I do plan to do the work permitted with the city and utilize an architect.  Assuming the size is 20' x 25' is 50-80K a reasonable ball park estimate?

I'd also be open to any local referrals or recommendations via DM

Thank You


@Darius Hoffman - Sounds like you have a potential cool project on your hands.  I'd definitely recommend talking to some smart architects like @Samuel Pavlovcik and @Prashanth Mahakali , they will be able to you with all the restrictions.  

$80k should at least be in the ballpark, but kind of tough to say.  No plumbing is a good thing but you'll still have the other mechanicals that adds up quickly.  Let us know how we can help.

Hey @Darius Hoffman , sounds like a great project to add some value to the residence!

A few notes to clarify your zoning questions:

- Your rear setback requirement will be 35'

-  Your open space requirement will be 225 sq.ft. with a minimum dimension (on each side) of 15' (15x15 square)

- Your side yard setbacks will be 2' minimum with a combined side setback of 5' This is important because if your existing building is closer to the property line than allowed by Zoning, you will need to in-set the addition to meet the setback requirements, or pursue an Administrative Adjustment in order to request to follow the existing exterior walls of the building. This isn't too difficult to obtain, but will add about $500 to your permit fees and possibly 4 weeks to your permit turnaround timeline.

- Check for an existing Cistern at the back of the house (may be under a rear porch). These are not uncommon for old houses in Chicago. Rerouting/terminating these could be an extra cost on the plumbing side that you were not planning for.

- Check for the location of where the electrical service connects to your house. If the new addition would overlap where your meter is located, or get in the way of an overhead power line, you may need to relocate your electrical service riser, and likely provide an electrical service disconnect due to the distance between the meter and the electrical panel.

I will send you a PM, I'd be happy to connect and discuss further. A Plat of survey would be helpful to verify the Zoning, and as a heads up, the City of Chicago wants one dated within 6 months of the permit application, so you may need to get an updated survey if it is not new.