Why We Need 'Distributed Density'

©. Image by Sali Tabacchi for Ryerson City Building Institute. Reproduced with permission

It is not just a choice between tall and sprawl.

Since the coronavirus hit, there has been a lot of talk about urban density being a factor. No matter that in New York City, where this has been thrown around a lot, Queens and Staten Island had far higher rates of infection than the far denser Manhattan, because the real correlation is with income, not density.

But what has become clear is that being in lockdown in high-density towers is a pretty awful experience, whether it is the lack of space or the shared elevators or the crowded sidewalks. That's why, in my earlier post, I talked about Brent Toderian's term, Density done well, or my Goldilocks Density.

Density done right

© Density done right

It is also why I was so intrigued by a new report from the Ryerson City Building Institute, Density Done Right, that calls for distributed urban density. It's a rejection of what most successful cities have now, which is "tall and sprawl" development.

Our current pattern of housing development has also contributed to a lack of suitable and affordable housing options within urban and suburban centres close to schools, transit, health and community services, amenities and jobs. Increased housing prices have already forced too many people to choose between squeezing into too-small condos and commuting to a home far outside the centre of the city.

We have discussed the problems of sprawl for years: the car dependence, the cost of servicing, the loss of farmland, and more recently, the carbon footprint. But there is also a real cost of tall: "Intense concentrations of high-rise development can place significant pressure on hard and soft infrastructure systems, namely transit, water, wastewater, parks, childcare and schools."

This is where my Goldilocks density came from; the idea that there was something in the middle. What the Ryerson CBI calls distributed density, a mix of townhouses, walkup apartments and midrise buildings at strategic urban centers and along transit corridors, neighborhood avenues and main streets.

Walk-ups and townhouses can offer many of the same amenities as single-detached homes, including ground-level entry and access to front or rear yards, while allowing for more density than single-detached homes. Walk-up apartments offer much-needed purpose-built rental units, which, unlike accessory units in single-detached homes, may not carry the same risk of being reconfigured into a single unit or of being removed from the rental market entirely.

All of this is what has been called the "missing middle" or "gentle density," those built forms that can double or triple the density of neighborhoods without going to high-rise structures. In many cities it is almost impossible to do this; single-family zoning restrictions let people build huge houses, big enough to accommodate three families, but are restricted by the bylaws to one. Or Main Street redevelopments that are uneconomic because of ridiculous parking requirements, even when the buildings are right on a streetcar or subway line.

Distributed density supports livability.

Increasing density stupports stores and businesses.

© Image by Sali Tabacchi for Ryerson City Building Institute. Reproduced with permission.

I noted in a previous post, Coronavirus and the future of Main Street, that more density might be a way of providing more customers, needed to keep our main streets healthy and vibrant. The Ryerson CBI says much the same thing:

Adding gentle density can help ensure there are enough people in a neighbourhood to support local schools, health and community services, and keep shops and restaurants open. It can provide a range of housing types and tenures that support the needs of individuals and families throughout all stages of life and allow for aging in place. It can also support public transit service, providing residents with efficient and affordable transportation options without relying on private automobiles.

Distributed density supports affordability.

affordable housing from distributed building

© Image by Sali Tabacchi for Ryerson City Building Institute. Reproduced with permission.

This one's personal: My wife and I were able to stay in our house, way too big for the two of us, because we were able to downsize into the ground floor and lower level, with the cost of the renovation essentially being covered by the rental income from upstairs. Zoning bylaws make it much easier to renovate than replace, where there are all kinds of additional fees, setbacks and other restrictions that make new housing hard to do. But in fact, new wood frame construction is the cheapest form of building, often less than half the cost of high-rise construction. If it was easier to demolish really crappy old housing and replace them with multifamily houses, we could dramatically increase energy efficiency, density and reduce carbon footprints.

Distributed density supports environmental sustainability.

environmental sustainability drawing

© Image by Sali Tabacchi for Ryerson City Building Institute. Reproduced with permission.

This one is pretty obvious to urbanists: Low density suburbanites have the highest carbon footprint, mostly attributable to auto use but also because houses are bigger and do not share walls.

Multi-unit (or multi-family) housing is generally more energy-efficient than single-detached housing. Research in the United States found that comparable households living in single-family detached units consumed 54% more energy for heating and 26% more energy for cooling than comparable households living in multi-family units.

Wood frame construction also has just about the lowest embodied carbon of any form of building, other than perhaps straw bale. So really, the sweet spot for energy and carbon-efficient building is low-rise multifamily housing.

Distributed density is healthier.

Different forms of density

© Image by Sali Tabacchi for Ryerson City Building Institute. Reproduced with permission

This report was issued during the pandemic but doesn't address it, yet it is an important part of the discussion. It's long been known that people who live in walkable communities are healthier and thinner. It is also known that the COVID-19 is particularly hard on the obese and the unfit. With distributed density, there will be a lot less driving and more walking and cycling than there would be in Sprawlville.

On the other hand, you wouldn't have the problems that people do in Tallville – the shared elevators, the lack of open space, the overcrowded sidewalks that have made life for people in high-rise towers so miserable during this pandemic.

There is nothing new about this kind of housing either; this is how much of Europe is built, as well as in streetcar suburbs around North America. It's cheaper, it's healthier and it's faster than almost any other kind of housing. It should be not just allowed, but it should be promoted everywhere.

Download Density done right. Prepared by Cherise Burda, Graham Haines, Claire Nelischer and Claire Pfeiffer, from the Ryerson City Building Institute.

Disclosure: I teach Sustainable Design at the Ryerson School of Interior Design, which is not connected to the Ryerson City Building Institute.