From 2015 to 2017, UrbanToronto and its sister publication, SkyriseCities, ran an occasional series of articles under the heading Explainer. Each one took a concept from Urban Planning, Architecture, Construction, or other topics that often wind up in our publications, and presented an in depth look at it. It's time to revisit (and update where necessary) those articles for those new to UrbanToronto. While you may already know what some of these terms mean, others may be new to you. We will be (re)publishing Explainer on a weekly basis.

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Last week we took a quick look at official plans and zoning. Both have been in the Toronto news more often recently because of talk spurred by our rising housing affordability crisis: between our Official Plan and our Zoning By-laws, it's very difficult to add new housing in Toronto. Most of the area set out in Toronto's Official Plan as residential is restricted by zoning to single family homes. On land use maps, that Neighbourhoods area has been traditionally represented in yellow, and has become known as 'The Yellow Belt', a term coined in 2016 by Gil Meslin, a Toronto planner in private practice. Instead of densifying in these areas, the City has wanted to concentrate new housing in nodes near rapid transit stations, and along the major Avenues. Existing zoning means, however, that every new building requires a drawn out negotiation with the planning department to get the necessary approvals.

Toronto's Yellow Belt, image by

While we concentrate new housing on a small percentage of our city's land mass, the protected Yellow Belt areas are losing population. Where streets mostly filled up young families when the homes were new, many of those homes now have only one or two adults living in them, causing the aging neighbourhoods to lose population. Just two services that are affected; school enrolment dwindles in these areas and fewer people pay to ride transit there, so some schools close and some bus routes have their service cut back. Where we do not allow new housing, neighbourhoods do not stay the same: they hollow out. Meanwhile, where we concentrate new housing, those schools are bursting at the seams and the transit is overcrowded.

Pre-World War II, Toronto allowed duplexes, small apartment buildings, and more to be built side-by-side with single family homes. This meant the city's form was more dense, and more akin to even denser cities across Europe, which manage to easily house more people in the same area while still being immensely livable. Rapid post-war development in North America, however, came with stricter zoning and and ended up creating a tale of two densities and extremes of housing that now dominate the cityscapes of Toronto and most of the continent's other biggest cities.

While single-family housing exploded in the suburbs, (creating a built form characterized by large lots and automobile dependency), until recently, high-rise condominiums and rental apartments fulfilled a demand for comparably inexpensive living within urban enclaves that support walking, cycling, and transit. Now those condos and rentals have also become unaffordable for many people, and the sweet spot provided by small multi-family buildings as become lost in the shuffle, leaving little room for the gentle density increases in hollowing-out neighbourhoods that could address much of the need.

Missing Middle Housing types, image via Opticos Design

This typology, the so-called 'Missing Middle Housing,' is what many urban advocates are striving to bring back into the fold. These multi-unit housing types – duplexes, triplexes, four-plexes, townhouses, and courtyard apartments – generally have a similar footprint to single-family dwellings. Because of its comparable physical dimensions, Missing Middle Housing can be comfortably integrated into blocks that are historically and predominantly occupied by single-family homes. The moderate densities these building typologies achieve can support an amenity-rich and walkable environment serviced by public transit. They play a massive role in helping cities reach their infill and density development targets. (A conversation about this taking place recently in Edmonton can be found here.)

Townhome development in Toronto, image by Marcus Mitanis

Some of America's most vibrant and hip up-and-coming communities embrace this concept. Changing demographic trends have shown that youth and seniors cherish easy access to services and amenities available in compact and transit-oriented communities. Millennials are driving less than their predecessors, and aging baby boomers increasingly want to 'age in place,' according to the American Association for Retired Persons. The convergence between the two cohorts is pushing a narrative for more diverse housing options. 

Missing Middle Housing in Toronto, image retrieved from Google Street View

An average physical footprint and small unit sizes can make Missing Middle Housing a lucrative prospect for developers, but outdated zoning and land use regulations often bog down the approvals process. Governments that are hoping to ease the housing crunch and prevent priced-out millennials from fleeing the city are gradually amending their planning policies and codes to allow for intuitive fixes like laneway housing, garden suites, and 'pork chop lots.'

While the talk about changing our zoning to allow Missing Middle Housing in our neighbourhoods is getting louder, there are other issues surrounding the Housing Affordability Crisis, and we will delve into them in upcoming UrbanToronto articles.

In the meantime, do you have other planning terms that you would like to see featured on Explainer? Share your comments and questions in the comments section below!

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