Sixplex Study for Ward 23

This study looks at the feasibility of six-unit multiplexes on a range of residential lots by looking at parcels within Ward 23 – Scarborough North.

Client:
City of Toronto

Date:
2024

Team:
Michael Piper
Sam Eby
Janna Levitt
Lola Abraham
Bradley Dunn
Josh Kirk

The Study

This 3-phase study demonstrates how multiplexes with up to six units can be built on a range of residential lots, using architectural case studies. For the purpose of this study, we focused on six-unit multiplexes, as they would have the greatest impact on unit creation, and used parcels within Ward 23 – Scarborough North.

Our findings outlined substantial potential within Ward 23 to accommodate six-unit multiplexes.

Download the report here or scroll down to view it below.

Phase 1: Framework

In this initial phase, we developed a draft framework that cross-referenced a range of parcel sizes with the minimum dimensions required to construct a six-unit multiplex. We surveyed 16,107 parcels under the RD, RS and RT zoning regulations, excluding corner lots.

We used a method of typological analysis to assess the number of lots suitable for six-unit multiplexes, as well as the quality of units and buildings that can feasibly be developed. The analysis cross-referenced a range of parcel sizes (widths and lengths) with the minimum dimensions necessary for a sixplex. The analysis shows that building proportion is dependent on parcel proportion.

We established this range of parcel sizes according to width, starting with a six-meter wide lot. We tested the minimum-size sixplex possible on lots with widths in two-meter increments: 6M, 8M, 10M, 12M, and 14M wide. For each width increment, we explored two parking scenarios.

After designing the minimum size sixplex for each lot width increment, we added the required setbacks and measured the required lot depth needed to accommodate the building. These lot depths provided the basis for a range of lot depths for each lot width increment.

Phase 2:
Case Studies

In consultation with the City, three parcels from Phase 1.0 were used to develop detailed designs to test the feasibility of sixplexes. Each case study focused on different site conditions, internal unit configurations, and parking arrangements. A drawing set was developed for each case study and submitted to the Building Department for review and comment.

• Case Study 01: Site Width: 12.3m | Stair: Scissor Stair | Parking: Integrated
  
  
• Case Study 02: Site Width: 10.64m | Stair: Stacked Townhouses | Parking: Rear Yard
  
  
• Case Study 03: Site Width: 7.9m | Stair: Front and Rear Stair | Parking: None
  

Click to see the Case Study designs! 

Phase 3: Revised Mapping

Following the completion of Phase 2.0, we revisited the mapping study and framework established in Phase 1.0. We adjusted the framework to reflect lessons learned in Phase 2.0 and to account for assumptions around softscape requirements.

Our findings suggest that approximately 6,629 lots, or 41% of the total we studied, can accommodate six-unit multiplexes, assuming the conditions outlined in the methodology are met. 

Finally, the report includes policy recommendations based on the findings of the study.

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