What Is a Garden Unit in Chicago?

A garden unit is an apartment that sits a few steps below the sidewalk. The windows look out at yard level. That is where the name comes from. Most of the country says basement apartment. Chicago has so many that they earned their own, nicer name.

You will find them under 2-flats and 3-flats all over the city. A 2-flat is a brick building with one apartment stacked on another. Many of them picked up a third apartment downstairs somewhere along the way.

Here is why buyers should care. Say you buy a 2-flat and live upstairs. If the building also has a garden unit, you can have two rents coming in instead of one, under the same roof, on the same mortgage.

The first question to ask: is it legal? Some garden units are legal apartments. Some were finished without permits years ago. You do not have to guess which one you are buying. Before a small building changes hands in Chicago, the seller has to get a paper from the city called a zoning certificate. It states how many apartments the building is allowed to have. If the paper says two units and you counted three, the garden unit is not a legal apartment. Your attorney sees that paper before closing, not after.

A garden unit that is not legal does not have to kill the deal. It can be family space or a home office, and the price you offer should treat it that way. And the city just opened a door here. New rules that took effect April 1, 2026 let owners in many parts of Chicago add a legal basement apartment with a permit. It depends on the ward, so it has to be checked address by address. We check that on any building we look at with you.

When you tour one, look at two things: water and light. Ask if the basement has flood control. It is a valve that protects the lower unit in heavy rain, and a building that has one was looked after. A legal unit also needs about seven feet of ceiling height. Garden units get less sun than the units upstairs, and they rent for less. Price the rent honestly and the math still works, and you can run those numbers on any building you are looking at.

Renters like garden units because they cost less and stay cool in summer. Buyers should like them more than they do. A second rent nobody brags about might be the most underrated thing in Chicago real estate.

Thinking about a building with a garden unit? Reach out. You do not need to know exactly what you want yet. Most people who reach out don't.