The Case for Density in Sustainable Cities

Brent Toderian's picture


In addition to Vancouver being included as one of the 10 global cities profiled in the Urban Land Green keynote article, "Greener Cities", prominent local sustainability consultant Mark Holland and I were asked to write an article about density and its relationship to greener cities. The article below resulted. As I often say and write, cities cannot have a serious discussion about sustainability without talking candidly about the key tool of density. We hope this article helps with your local discussions.  


The Case for Density

By strategically increasing the number of dwelling units per acre, cities not only will go a long way toward meeting their sustainability objectives, but also will be competitive, resilient, and great places to live.

Urban Land Green - Spring 2008                                                                                         

By Brent Toderian and Mark Holland 

Density has become a highly charged topic in development today. In many communities, the news of a potential project that proposes to increase the number of dwelling units per acre can unleash an uproar by neighbors. This is unfortunate as density is a tool-arguably the most powerful one controlled by a municipality-to create a more sustainable city while at the same time helping to preserve agricultural land and the open space beyond its borders. Furthermore, strategic densification offers positive benefits far beyond an individual metropolitan area: after all, given the continued growth in world population and the continued migration of people to cities across the globe, the densification of all urban settlements-when done properly-can play a critical role in improving the health of the planet as a whole. 

Over the past several decades, the city of Vancouver, British Columbia, has applied strategic densification and increased housing choice in an effort to build a livable city of neighborhoods. In doing so, it has strengthened what many urban analysts consider to be the eight pillars that support a sustainable city. These pillars, and the contribution that density makes to them, are described below. 

Pillar 1: A Complete, Walkable Community

A sustainable community needs to be structured into complete, well-connected, mixed-use neighborhoods that allow residents to work, live, play, shop, and learn within a convenient walking or transit distance. While communities should be fashioned so that key natural features are protected, these should not be at the expense of many connections within neighborhoods to facilitate short trips between uses. A diverse mix of housing reflecting a range of incomes, family sizes, and ages should exist. Commercial areas should offer office, retail, and commercial space, in addition to residential and community amenities. 

Density that is well designed and assembled makes transit and retail more viable, supports more schools and services close to homes, and supports the clustering of development so as to better preserve natural areas. Higher densities make walkability possible, and great design makes it enjoyable. 

Pillar 2: A Low-Impact Transportation System

A sustainable community should provide as many alternatives to the automobile as possible, including planning for convenient transit service, and supporting shared-car opportunities to reduce the need for single-person auto use. Parking strategies should gradually reduce car use and ownership, and parking design should minimize landscape disruption.

A sustainable community should also prioritize pedestrian and cyclist modes of mobility by linking all areas with a fine-grained network of paths, and by designing local streets to support all ways of getting around, rather than emphasizing vehicular needs. Streets should also address other environmental and social objectives such as stormwater management, trees and bird habitat, urban agriculture, and playground areas. 

Research has shown density to be critical in shifting transportation away from the automobile to other modes of travel. With 30 to 60 percent of climate-changing emissions coming from transportation, this is critical. The emerging most influential neighborhood planning tool, the U.S. Green Building Council's (USGBC) LEED for Neighborhoods (ND), notes that a minimum of seven dwelling units per acre is required to support one bus every 30 minutes. Significantly increasing ridership requires transit frequency of around ten to 15 minutes, which in turn requires urban densities of 20 to 40 units per acre on average within a few blocks on either side of any key transit line. Highly convenient rapid transit requires even more units per acre to be viable. 

Pillar 3: Green Buildings

Buildings stand for 50 to 100 years, often with relatively few modifications, and their design significantly influences the impact their occupants have on the planet as they go about their daily lives. A sustainable community should be filled with green structures, which are typically promoted through green design regulations or guidelines or through green building rating systems such as the USGBC's/CaGBC's LEED system.  

Density necessarily requires a high percentage of multifamily homes in a neighborhood. Multifamily residences can be significantly more energy efficient than single-family homes as they share walls and often more efficient building-scale heating systems. Furthermore, multifamily densities are required to make the construction of district heating systems financially viable. In other words, some of the best green design and technological approaches are highly dependent on mid to higher densities. 

Pillar 4: Flexible Open Space

The open space in a sustainable community should accommodate both community and ecological needs, including protecting key environmental areas or functions, enhancing habitat through urban landscape design, offering significant recreation opportunities for people of all ages, and providing places to grow food in the city.  

Density offers both benefits and challenges in this regard. Parks, community gardens, and other open areas compete for space in a high-density neighborhood. The land these uses occupy requires significant civic investment unless a developer has provided them as a condition of development. However, through the use of green roofs, courtyards, and other exterior elements, well-designed density can provide strategic opportunities for outdoor space and locations to grow food. In addition, from a larger-scale view, focusing growth within higher-density areas permits the preservation of farmland, riparian areas, and other key uses on the edges of the community.  

Pillar 5: Green Infrastructure

"Green" infrastructure strategies should be created for every sustainable community to address the supply and management of energy, potable water, and materials and the reuse or disposal of wastewater, stormwater, and solid waste. Ultimately, many benefits can be gained by integrating these systems. For example, heat harvested from a wastewater pumping station can be used to heat buildings. The 2010 Olympic athletes' village in Vancouver, for instance, will be heated entirely by the heat from one wastewater pumping station nearby. 

Denser development provides the demand for heating and cooling that makes innovative infrastructure systems financially viable. For example, density around energy sources creates opportunities for cogeneration, from large facilities such as hospitals and arenas, or infrastructure such as transit tunnels. Waste energy from mixed uses can also provide opportunity for efficiency and utility investments, such as harvesting waste heat from a supermarket's freezers on a ground floor to heat residences above. Since a significant amount of greenhouse gas emissions are attributable to heating systems, any opportunity to establish district heating systems should be pursued in cities, and density and mixed uses make these uses more viable and profitable. 

Pillar 6: A Healthy Food System

A sustainable community includes food stores and restaurants, along with the provision of community garden space in neighborhoods. Some studies have suggested that as much fuel is used in a year to get a family's food to the table as is used by that family for all their other activities put together. Furthermore, the visibility and celebration of food in a neighborhood is an excellent source of social and cultural vitality-an important aspect of sustainability that should not be overlooked.  

Dense developments support local food stores and restaurants, community gardens, and other creative food-producing ventures, thereby offering residents convenient access to basic provisions. As noted earlier, compact, sprawl-reducing density can also support regional preservation of key, nearby agricultural areas. 

Pillar 7: Community Facilities and Programs

A sustainable community should provide key community facilities to support a healthy lifestyle, and the creation of diverse and positive social experiences for people of all ages. This includes a high-quality public realm that is designed to promote safety and encourage residents to meet each other and build relationships.  

Denser development leads to a much stronger business case for both public (e.g., community centers, parks) and private (e.g., supermarkets, coffee shops) amenities and programs. It also fosters a public realm that is able to generate high-quality activities that encourage the interaction of neighborhood residents. 

Pillar 8: Economic Development

A sustainable community should offer many ecologically responsible opportunities for investment, businesses, and employment that will, in turn, support an economically diverse and prosperous community. A range of commercial (office and retail) facilities should be offered to maximize working and shopping opportunities.  

Well-designed density is vital to a strong economic foundation in any neighborhood as it brings a critical mass of local employees and customers to support a variety of community needs. 

Sustainable cities are complex, and there are many factors to consider. Density is one of the most powerful tools any municipality has to achieve sustainability in all its dimensions. The 21st century will be the century of densification, and cities that get it right will not only perform well on sustainability objectives, but also be competitive, resilient, and great places to live.  

Brent Toderian is the City of Vancouver's director of planning. He is responsible for current planning, including the planning of projects for the 2010 Winter Olympic Games and policy and visioning, including the city's EcoDensity Initiative. Mark Holland is a sustainable development consultant working with developers, cities, and companies. He has been a city planner in Vancouver and was the first manager of the city's Sustainability Office. 

* * * 


Vancouver's EcoDensity Initiative 

Building on its past successes in policy and projects involving well-designed density, the city of Vancouver launched an initiative, dubbed "EcoDensity," in 2006. This initiative embraces additional population growth within the city limits, done in a way that lowers environmental impact, supports sufficient physical and social amenities, and fosters housing diversity and affordability. 

Densification effects change, so discussions of density always raise debate. Even in Vancouver-a city in which density has been done well in the past-concerns have been expressed that this is "eco-cramming." Some say the price of change is too high-that it will reduce the quality of life, promote gentrification, decrease affordability, and change the character of the city's neighborhoods. Others, however, champion the notion of "density done well" and point to the price of inaction: a growing lack of affordable housing and housing diversity, given that about half of the city land area is still zoned for single-family homes, and the ongoing challenge presented by global climate change. Although the resulting public debates have been challenging, they are necessary and healthy for any city intending to take ecological sustainability seriously. 

Vancouver maintains high standards of urban design in denser areas to overcome the challenges posed by densification. The city also has a tradition of negotiating public benefits from developers in the form of community amenities. The combination of high-quality urban design, private provisions for public amenities, careful siting of new density types and scales relative to context, an emphasis on diversity, and engaged public discussions will continue to be the path that the city takes to move forward.-B.T. and M.H.





One of the fundamental principles of “Smart Growth” is to increase residential density by infill in existing areas, and by redeveloping existing residential areas more densely. The claim is that this will somehow create livable cities, reduce energy requirements and emissions, save farmland, and protect green space. Or, as the U.S. Environmental Protection Agency puts it, “density is (an) integral component to the creation of neighborhoods that offer convenience, value and a high quality of life.” (

Portland, Oregon, is an icon for the smart growth social engineers. In a 2007 article about problems with the Portland harbor ( , the Portland Tribune cites a recent study by the Portland Business Alliance and state agencies which shows that the number of goods passing through Oregon needs to double by 2030 to keep pace with population growth, globalization and expanding markets. But the harbor and city infrastructure are lagging. Traffic congestion and delays on Portland roads are cited as hindrances to business efficiency, and as a significant factor in increasing business transportation costs.

What is the proposed solution? More harbor facilities, and significant improvements in rail and road infrastructure through Portland. That’s right - an infrastructure deficit, traffic congestion, and more roads, some of the very things that smart growth is supposed to help prevent.

The argument could be made that, as a port city, Portland is a special case. But Vancouver, B.C., is another port city, and has been called “the Northwest’s smart growth leader.” ( Here is a typical calculation of the ecological footprint of Vancouver: “When the calculations are made based on average Canadian consumption patterns, Vancouver (covering only 114 square kilometers) has an ecological footprint (appropriated carrying capacity) 207 times its actual size - an area covering 23,600 square kilometers. This includes 7,000 square kilometers for food production, 3,000 square kilometers for forestry products, and 13,000 square kilometers to accommodate energy use.” (

These results are similar to the calculations made by William Rees, co-developer of the ecological footprint concept, for Vancouver, and are similar to calculations made for Toronto, Ontario. In general, these relatively dense cities (by North American standards) have an ecological footprint about 200 times their actual geographical size. That footprint includes, among other things, appropriated farmland in other countries which supply our food, land used for industrial development in other countries which supply our goods, and land used to supply energy in those countries and deal with wastes.

If density is the criterion, then Los Angeles is near the pinnacle. L.A. has one of the highest urban densities in the United States. Yet farmland and natural space around the city continue to disappear. And L.A. continues to have some of the highest rates of traffic congestion, and of poor air quality, in the United States.

What then is wrong with the smart growth argument? Fundamentally, the energy and food requirements for suburban subdivisions and for very dense urban development are approximately the same. Indeed, many highrises use more energy per resident than a well-built townhouse, and not much less than a small well-built single family home. The Canada Mortgage and Housing Corporation states that, “on a floor area basis, (highrises) consume more energy than single family dwellings - even though the highrise unit has much less exposed exterior surface. And when compared to the leading edge Advanced House standards for energy consumption, multi-unit residential buildings consume three times the amount of energy per unit of floor area.” (

With dense development, the food must come from farther and farther away. Each new person requires additional farmland somewhere else in the country, or on the planet. And the denser the development, the farther the food must be transported. In the words of William Rees, “cities necessarily appropriate the ecological output and life support functions of distant regions all over the world through commercial trade.” ( )

Then there is the issue of the “degraded land” portion of the ecological footprint. Degraded land is the land required for buildings, driveways, roads and highways, parking lots, businesses, public buildings, industrial infrastructure, railroads, airports, and garbage dumps (before reclamation, of course). A residential lot in suburbia is only a tiny portion of the degraded land footprint. Even highrise dwellers still require virtually all of that infrastructure, including highways and roads to escape the city for recreation (as there aren’t many golf courses and ski hills in the downtown cores of most large cities) and to bring in goods and services. As an example, those of us who live in British Columbia’s Okanagan Valley and Shuswap area know full well how many Vancouverites, Calgarians, and Edmontonians drive hundreds of kilometers on a regular basis for our recreational opportunities, putting more and more pressure on our natural areas as the populations of those cities continue to grow. Highways and roads seem to be under construction continually as traffic increases, with lanes added each year.

And silently, unknowingly, those urban Canadians are accomplices in other activities leading to resource exploitation in natural areas, and to creation of even more degraded land from industry and commerce, accompanied by even more waste and pollution.


Growth in the value of their stock portfolios, RRSPs, mutual funds, and pension plans relies heavily on these sorts of activities, even growth in many of the so-called “ethical” funds and investments. Yes, rural residents have the same issues, but the bulk of our population is in cities. This is just one more example of how the call for even more urban growth, through densification, has an impact on the planet – an impact that is hidden from those creating it. Out of sight, out of mind, but every little bit hurts.

There are those who say that “Peak Oil” ( ) will help to alleviate many of the failures of smart growth. People will be forced to drive less, we will have to use alternative energy sources, and (one of the important points) we will have to relocalize production of food and other commodities – the 100 mile diet ( ), and so on. But cities like Vancouver, hard up against other cities already, will find it impossible to do so, as there simply isn’t enough agricultural land left within easy transportation distance to supply all the needs of the residents, especially when the adjacent cities of New Westminster, Surrey, Coquitlam, Langley and so on are all growing rapidly themselves.

There are even predictions of the complete demise of large cities in a post-carbon world, with claims that villages and small cities with populations up to 80000 people will be the only urban forms able to sustain themselves with what they find locally. ( ) Predicting the future is a risky and uncertain business, but the promoters of smart growth certainly don’t have a monopoly on the truth.

Those who are coming to grips with the fact that current alternative energy sources still rely quite heavily on fossil fuels for materials, manufacture, transport, and maintenance and cannot supply all of our energy needs are pinning their hopes on Plan B: technology will somehow come up with a clean and cheap energy source that will be as portable, energy intensive, flexible, and reliable as fossil fuels. Such an energy source is nowhere on the horizon, and already alternative energy sources are showing themselves to be extremely expensive, and often unreliable. It is at least possible that the smart growth engineers may be creating the conditions for catastrophe if Plan B fails.

Just like the efforts of conservationists, hopes of saving farmland and natural spaces through dense urban development are doomed by population growth. Each additional person consumes more goods, land, food, energy, and degraded land. Each additional person places more pressure on natural areas and adds more risk to threatened species, not just locally, but across the planet; the human-caused “Sixth Great Extinction” of species is happening now ( Even in Canada, biodiversity is on the wane, with many species already extinct or threatened. And, finally, each additional person creates more waste and emissions.

By hiding, or ignoring, or trying to discount these impacts, the smart growth social engineers are covering up the ecological destruction that they are creating. Calling it “eco-density,” as Sam Sullivan, former mayor of Vancouver did, is more than just invoking an oxymoron; it is a complete eco-obscenity. “Grow up, not out” is the mantra of many local politicians, and of course developers are happy to oblige. But empty catch-phrases and slogans like this have somehow convinced us that we can feel good about population growth as long as it is “planned” properly, and directed to denser development.

And the slogans and good feelings are hiding the fact that we are creating something much, much more destructive for this planet than urban sprawl – something that is rapidly destroying other species, depleting resources, gobbling up farmland and natural space, and polluting the land and the water and the air. What we’re creating can only be called human ecological sprawl.

(Postscript: I wrote this last year, but note that in the meantime Vancouver has become notorious as the gang and murder capital of Canada. So much for a "walkable" community if you're always in fear of getting gunned down while walking to the local store. From Vancouver's pollution of the Fraser Valley airshed, to its congested streets and "freeways" (a.k.a. "rush hour parking lots"), to it's enormous social problems, it is about as far away from a model of sustainability as it gets. Another empty catchphrase, "moving forward," is invoked by the author of the article above to obliquely acknowledge that problems exist, and to somehow imply that the problems will all magically disappear if only we cram more people into less space. Call them urban feedlots for humans, termite colonies, an anthropocentric conceit, or what-have-you, large cities are an unsustainable form. Period.)

Energy Requirements


You are only thinking about energy requirements for the residence itself. You are ignoring the energy requriments for transportation, which is where smart growth advocates say the major savings are.

Charles Siegel

The meaninglessness of comparing energy use based on floor area



Charles Siegel"

Furthermore, there is no basis whatsoever to compare housing types based on energy use per unit of floor area, as in the cited article. It is completely meaningless because different housing types are inhabited at different rates of floor space per capita. In particular, you will find a lower level of inhabited floor space per capita in densely populated neighborhoods than in sparsely populated neighborhoods.

Apples and grapes.

"Furthermore, there is no basis whatsoever to compare housing types based on energy use per unit of floor area"

So, you're saying that the claims by the so-called "smart" growth crowd about a reduction in energy use have no basis?

Housing types and energy

I'm not certain which crowd is making which claims, but all I'm saying is that if you are going to compare energy usage in different housing types, the comparison needs to be per capita rather than per unit of floor area to be meaningful.

I think you agree, because you elided energy use per capita and energy use per floor area in your summary of the article. Quote:

You introduce the quote by saying highrises use more energy per resident, but the quote itself refers to floor area.

AFAIK, there is no rigorous study on energy use per resident in different housing types. I would like to see one, because then we would have some real data to base this discussion on. Intuitively, I believe that on average, people in densely settled neighborhoods occupy less floor area per person than people in sparsely settled neighborhoods. I admit that this is intuitive, but it is commonsensical enough that I and many others would need to see some data to change this belief.

Lastly, I will point out that many of your sparring partners on this board primarily advocate for densification by building small lot single family and townhouses, rather than highrises.

Yes, perhaps it's time for our civilization to get real.

"...because then we would have some real data to base this discussion on."

Yes, real data would be useful -- real data about the psychological and social effects of urbanization and densification, real data about the carrying capacity of the planet, real data that will not be taken out of context (or selectively ignored) so that the larger picture is considered, rather than the wishes and dreams of the would-be social engineers we call "planners."

Some real data may include the "Sixth Great Extinction" event and loss of biodiversity, the amount of arable land paved over on an annual basis, the total increase in energy consumption and emissions (rather than per capita data), the sustainable carrying capacity of the planet and the amount of population overshoot, the minute difference "building small lot single family and townhouses" likely makes in our ecological footprint, the true effects of "Peak Oil," the insidious effects of technomania, and a host of other items which may have an impact on how we look at our current "civilization," and on how this sort of discussion may unfold.

Housing types/ carbon footprints/ energy use/ subsidized parking

Jon Petrie

1) In Vancouver "multifamily densities" usually imply concrete and steel towers. I wonder if any studies have been done of the carbon footprint per square meter of such construction compared to a) new wood frame construction and b) in-fill/ retaining older buildings.

2) My impression is that a substantial per cent of newish condo space in Vancouver is unoccupied most of the time -- the condos are second/ third homes and investments/ bolt holes of offshore owners. So I wonder about the life cycle carbon housing footprint per actual full time resident in a newish ecodensity tower.

3) In the article Mr Toderian makes no mention of how parking requirements indirectly subsidize/encourage car ownership in 'complete, walkable communities.' No surprise really, the thinking in Vancouver about parking is still 20th century -- Vancouver's recently opened 98 unit market rental housing tower is 100 meters from five bus lines, the monthly rent for parking ($35) is hugely below cost recovery (about $250). And in the marketing of the apartments transit is never mentioned but 'secure' or 'underground' parking is mentioned in every ad. For more on that particular Leed certified project

"Smart" growth and wasted energy.


Charles Siegel"

Actually, I am not, as there are additional energy requirements for transporting food and goods longer distances as density increases. And these people have to travel farther and farther, on more and more congested routes, for recreational opportunities that involve any sort of natural setting. As for the claim about "major savings" in energy, I'd like to see some conclusive evidence that that has happened anywhere. In a response to a letter I sent to the Premier of British Columbia, I was assured that energy requirements for Vancouver will continue to grow significantly. There was no mention of any "major savings" from any initiatives.

Are you again hiding behind the "per capita" smokescreen, and failing to look at total energy use? Might it be more appropriate for you to say that "smart" growth advocates say that there may be a modest reduction in the INCREASE in energy use, but there will still be an increase? That seems to me to be a more intellectually honest statement.

Please don't repeat yourself

Request that Planetizen editors block repeat posts.

The above was recently posted, verbatim, less than two weeks ago:


"Please don't repeat yourself
Submitted by isoquinophlex on Tue, 04/28/2009 - 10:36.

Request that Planetizen editors block repeat posts.

The above was recently posted, verbatim, less than two weeks ago:"

Given the excessive repetition of the so-called "smart" growth arguments on this forum, I saw that as license to repeat my A"S"G message. Next time, I'll just link to my original post. Thanks. Oh, and in case you hadn't noticed, it was not verbatim. I gather that you didn't read the addition at the end.

Tim Halbur's picture
Blogger / Alum

Please limit post length


I won't delete your post, but would ask that you keep your posts to 4 paragraphs and under.



Thanks, Tim. That's very reasonable, and will do. And I will not do what James Joyce did and write the longest paragraphs in the world.

Will increasing Vancouver's population make it more sustainable?

Toderian and Holland say "Density is a tool ... to create a more sustainable city." Perhaps that would be the case if the population of Vancouver were kept stable, and that some agricultural land were reclaimed by residents on those lands relocating to more compact neighbourhoods. But no, what these two are talking about here is increasing the total population of Vancouver by putting newcomers into high density neighbourhoods. Increasing the overall population of Vancouver will make it LESS, NOT MORE, sustainable regardless of the densities created.

In 2005 Anielski Management consultants prepared a report for the Federation of Canadian Municipations entitled The Ecological Footprint of Canadian Municipalities and Regions. In that report they calculated that Vancouver residents have an ecological footprint of 7.71 hectares PER CAPITA compared to our global biological carrying capacity of only 1.90 hectares PER CAPITA, making that footprint 4 times what can be sustained globally. And with the Vancouver CMA having a population of roughly 2 million people and occupying 287,900 hectares of land area, Vancouver's total ecological footprint is 15,420,000 hectares or 54 times its land area. Can someone please explain to me how increasing Vancouver's population, regardless of how the densities are arranged, will make Vancouver or any city, for that matter, more sustainable as I fail to follow Toderian and Holland's illogic?

"The world is no longer divided by the ideological 'left' and 'right', but by those who accept ecological limits and those who don't." -- Wolfgang Sachs

Implementing Density

I concur with most of the "Case for Density" as put forward by Brent Toderian and Mark Holland. I would add a few points.
First, most people have an emotional aversion to the word "density." When we say "density," many people visualize tenement slums. They tend not to visualize the high-rise neighborhoods adjacent to Central Park nor do they visualize places like Georgetown or Annapolis. We know people like these places because they command high prices and folks like to spend vacation dollars there. We need to take note of this emotional situation and use words that do not create negative feelings. Instead of using "density," we can say that these neighborhoods are "vibrant" "convenient" "exciting" "lively" "active" "accessible" "livable" "productive" "pedestrian-oriented" etc.
Second, while density has advantages, there are many regulatory and financial incentives that encourage sprawl. Fortunately, there is a tax technique that creates financial incentives for more compact development. This technique involves reducing property tax rates on buildings and increasing property tax rates on land. It's not intuitively obvious how this works, but folks can download a brief two-page article, "Tax Reform Promotes Sustainable Development" from my web site at .

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