Land use planning according to what you can versus can't do
May 31, 2025
I got a notice in the mail this week for a public meeting related to Toronto's multiplex zoning by-law. Multiplexes are house-like buildings with two, three or four dwelling units. This housing type became newly permissible across the city in May 2023, but as part of the approval, the city was asked to keep an eye on things and report back on anything that might need to be changed. What is now being proposed are amendments to this original by-law.
One change is the introduction of the term "houseplex." This is meant to get away from unit-specific terms like duplex, triplex, and fourplex; but it also sounds like it was designed to placate single-family house owners. Another proposed change is a limit on the number of bedrooms in a building. For houseplexes with three or more units, the maximum number of bedrooms is proposed to be 3 x the number of dwelling units. This is designed to block rooming houses.
It's a reminder that zoning is, at least in this part of the world, about fine-grained control. It's typically about narrowing the universe of options down to a minimum so that it's clear what we can expect. This is why zoning by-laws have things called "permitted uses." It's a strict list of things you can do. And if it's not on the list, it's off limits. A different and more flexible approach would be to do the opposite: list only what you can't do. This broadens the universe of possibilities, but gives up some control.
Roughly speaking, this is how zoning works in Japan. Land use planning starts at the national level, as opposed to being strictly delegated to local governments. And from my understanding, there are 12 main zones, ranging from exclusively low-rise residential to exclusively industrial. (Here's an interesting undergraduate paper I found on the topic.) What's fascinating about this system is that it's organized by nuisance or intensity level, and it works cumulatively.
Meaning, as you move up in allowable nuisance, things of lesser intensity still tend to be allowed. For example, just because you might have a commercial zone with restaurants and department stores, it doesn't mean you still can't build residential. It's a less intense use. At the same time, the starting point is also more permissive, because even the exclusively low-rise residential zone allows "small shops or offices." What all of this creates is a planning framework where most zones are by default mixed-use.
This is a fundamentally different approach. It relinquishes some degree of control, embraces more flexibility, and accepts that cities are chaotic living organisms. It's impossible to draw lines on a map and figure out exactly where each permitted use should go. We'll never get it right and/or keep up. What this means is that we're artificially stifling our cities by not just focusing on the obviously bad stuff (like heavy industry next to a daycare), and letting the market decide where a ramen stand should go.
Cover photo by Susann Schuster on Unsplash
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