St. Clair West Fourplex Conversion

Build X Design | Fourplex Conversion

One Shell, Four Homes.

This semi-detached house in St. Clair West Village sat on the market for months before Build X’s client picked it up, mostly because of an open building permit that scared off other buyers. Everyone assumed something structural. It turned out to be a stair. Once we confirmed that in due diligence, the client negotiated a serious discount on a property nobody else wanted to touch.

The conversion splits the main building into four units stacked by floor: a one-bedroom in the basement, a one-bedroom on the ground floor, a two-bedroom on the second floor, and a one-bedroom on the third. Each has its own entrance, a front stair up to the top unit, two rear doors for the main floor and basement, and a new exterior metal stair built specifically to reach the second floor. The existing garage became a fifth unit, a studio garden suite, using a right-of-way easement to the side street that made the conversion possible in the first place.

The basement ceiling heights were fine for a legal duplex, but fell short of the code minimum for anything triplex and up. This normally means underpinning the whole foundation to gain the height. Instead, Our Build X team found a solution to split the project into two permits: legalize the basement as its own two-unit property first, then apply separately to convert the rest of the building into four units. That sequencing avoided underpinning altogether and saved the client 50 to 70 thousand dollars.

Project Type

Fourplex Conversion

Location

St. Clair West Village

Scope

Design + Permit

Year

Complete 2025