[getsmart-l] Low-rise Townhouses out-perform High-rises for cost, efficiency and humanity!!
John O'Gorman
jcogorman at sympatico.ca
Wed Feb 13 20:57:26 EST 2008
Faulty Towers
Edmund P. Fowler ?Alternatives Journal 34: 1 2008
St Louis, Missouri's infamous Pruitt-Igoe public housing project was less than 20 years old when it was demolished. Once heralded as architectural innovations, the 33 II-storey apartment buildings had become nuisances and danger zones. In 1972, after spending more than five million dollars in failed attempts to cure the massive project's physical and social problems, three high-rises were demolished in a broadly publicized event. A year later Pruitt-Igoe was declared unsalvageable and the remaining buildings were razed to the ground. Some experts marked this event as the end of Modernism.
See Pruitt-Igoe before and after the destruction in clips from Koyaanisqatsi [Life Out of Balance], a haunting film of urban and landscape images set to the music of Philip Glass: www.youtube.comjwatch?v=DHKhk4oZMro
THINKING OUTSIDE the box is a metaphor that refers to mental boxes such as preconceptions and unexamined assumptions. However, most cultures have tangible physical boxes as well as mental ones. These boxes take the form of settlements and individual buildings that influence our thoughts as well as our behaviour.
Unfortunately, our built environment is largely invisible to us because, like the dirty air we breathe, we are immersed in it every day. Noticing the built environment is especially challenging in North America, where homogeneous urban smears deaden our senses. Huge subdivisions, clusters of look-alike apartment towers, and shopping malls with all the same box stores discourage us from imagining anything else. We're learning that this landscape carries with it enormous social, economic and ecological costs, and it's high time to start thinking outside these physical boxes we've built for ourselves. One of these boxes is the high-rise.
At a time when we are trying to make cities more compact and therefore more environmentally sustainable, residential high-rises appear to be a grand way to increase urban density. Dozens of 25-, 30-, even 50-storey buildings, most of them condominiums, are being built not just in the downtowns of cities including Vancouver, Calgary, Toronto and Montreal, but also in their suburbs, far from high-capacity transportation such as subways and light rail transit. Developers, the councillors who support high-rises, and many planners describe these tall buildings as central to a vibrant downtown that contributes to a city's vitality. Even Jane Jacobs has been invoked as a fan of them, though she was not, as anyone who reads her book The Death and Life of Great American Cities will discover.
Economic and Environmental Costs
It is distressing to observe this uncritical acceptance of so many tall buildings, since from almost any perspective, they are expensive, both ecologically and economically.
The Housing Development Administration of New York City compared the costs of three-storey homes that are occupied by three families with high-rises. Both had the identical density of 125 units per hectare, proving that moderately high densities are achievable without tall buildings. Their study found that construction costs per room were nearly double in the high-rises, and maintenance costs were up to 50 per cent more. Similarly, the Canadian Mortgage and Housing Corporation (CMHC) reported in "Using Building Form and Design" that high-rises cost more to build per square metre.
These studies offered a number of reasons for the higher building and maintenance costs. Perhaps most importantly, high-rises are made from steel and concrete, which embody far more energy than the wood used in smaller structures. Moreover, high-rises use more materials and energy per square metre of usable space. In addition, features such as sprinklers, underground parking, elevators, and complex cooling and heating systems require costly construction and maintenance.
Once built, high-rises use more energy per resident than any other building form, including single-family homes. The "Multi- Unit Residential Building, Energy and Peak Demand Study," a report completed by EnergyAustralia, one of that country's largest energy suppliers, found that high-rises produced two-and-a-half times more greenhouse gas emissions per resident than townhouses (an indicator of high energy use). Experts such as Martin Laplante, an Ottawa-based planning consultant, say US findings are analogous. No one is really sure why tall buildings are so inefficient, although elevators and amenities such as swimming pools and parking use extra energy. Laplante adds, "As a building ages and small leaks develop in the shell and in ducts, you need more energy to push the air around properly and to heat, cool and dehumidify it." A CMHC study of an extensive energy retrofit on a Toronto high-rise showed that it would take 147 years for the owner to recoup the money spent on the renovations.
Thus, older high-rises develop problems that can discourage maintenance. One way of dealing with this situation is to sell old buildings, as the owners of Toronto's infamous St. James Town development did. Another is to set up the building as a condominium and pass along high maintenance costs to individual unit owners. Such "solutions," however, don't change the fact that, as the years go by, keeping the building in good shape becomes more and more onerous.
Furthermore, high-rises have notoriously short life spans compared to other buildings. In Housing for People, John Turner remarks that few tall buildings last more than 40 or 50 years, while smaller walk-ups or warehouses often remain in service for centuries. These same warehouses and other small buildings are also more easily adapted to creative new uses, whereas high-rises are not nearly as flexible. They often end up presiding over stagnant neighbourhoods. Laplante notes that "Concrete buildings are not adaptable - you can't even move a toilet, much less convert anything."
In Optimizing TOD (Transit-Oriented Development) Housing Mix and Density, Laplante reports that in neighbourhoods of medium to high densities, high-rise residents drive their cars more than residents of single-family dwellings and townhouses. The reason for this finding is unclear. However, high-rise clusters often do not contain a small-scale land-use mix that makes it easy for residents to walk to the store. Furthermore, since the rest of our cities are built to accommodate cars, it is quite likely that high-rise residents will drive to work, even if they live on a transit line.
While providing high-rises with water, police, fire, and other municipal services is cheaper per unit and per person than providing these services to detached houses, according to studies reported in my book Building Cities That Work, walk-ups and row houses are even less expensive to service than high-rises.
Architects and planners divide the floor area of buildings on a plot of land by the land area, to measure what they call the floor area ratio. The architect Jack Diamond told the Canadian Urban Institute (see Ideas That Matter, 4:1) that above a floor area ratio of 2: 1, savings on public services are marginal. In fact, according to Diamond, the city of Vienna, with a citywide floor area ratio of between 2: 1 and 3: 1 and only a scattering of high-rises, fits 1.6 million people into a space roughly eight per cent of the size of the amalgamated City of Toronto (population 2.5 million). "Vienna;' said Diamond, "supports effective and convenient public transit;' whereas Toronto is now building either high-rise condos or low-density detached dwellings, which is an overwhelmingly expensive combination in terms of public services.
Social Costs
Although few planners or builders believed her, Jane Jacobs pointed out years ago that there are many troubling social impacts of stacking dwellings up 20 and 30 stories. A number of studies, summarized in Building Cities That Work, have shown that high-rise residents have less contact with their neighbours than people who live in three and four storey walk-ups or row houses. Moreover, Albert Mehrabian, in his book Public Places and Private Spaces, reported that British soldiers and their families placed at random in high rises had 57 per cent more neuroses than those placed in single-family homes. Furthermore, the neuroses got worse at higher floor levels.
Because there are so many anonymous and usually empty spaces such as stairwells, utility rooms and parking garages in these buildings, even sophisticated monitoring devices can't prevent assaults and robberies. In general, the higher the building, the more the crime, regardless of the residents' income or ethnic background. Oscar Newman demonstrates this statistically in his 1973 book Defensible Space, for those who are not convinced by Jacobs' "anecdotal" evidence.
Because children are captive in their physical environment, they are especially influenced by it. Newman showed that juvenile crime was highest in the tallest buildings, a reality confirmed by my own research. I also found that children in high-rises were less free to explore their neighbourhoods and more likely to be fearful of their surroundings. They had fewer friends than children in walk-up apartments and townhouses that were set in physically diverse neighbourhoods. Bill Randolph, in his study Children in the Compact City, discovered that those who lived in high-rise flats were seriously restricted in their freedom, because parents thought it too dangerous to let them roam and explore. He concluded, "The net result was young children entering preschool or even school with poorly developed social and motor skills:'
Outside the building, sidewalk life is weakened by high-rises. The extensive security provisions and the distance of residents from the street create barriers to their joining activities on the sidewalks, most of which are not dangerous to, but supportive of, casual interaction among neighbours. This interaction, Jacobs found, nurtures informal support networks that are essential to a healthy neighbourhood. My own research has shown that areas dominated by high-rise buildings have less robust social networks and higher crime rates, no matter what their social, economic or ethnic characteristics.
Building with an Ecological Imagination
While the economic and environmental costs of the high-rise are not trivial, their social costs are arguably more significant. Both, however, are only symptoms of a more grievous failure. By cutting their inhabitants off from the physical urban environment as well as from casual social contact, high-rises contribute to the loss of an ecological imagination, thereby severing connections between human society and the rest of the biosphere.
Fortunately, contemporary European cities and some older North American districts demonstrate that extremely compact, mixed-use neighbourhoods are possible without going any higher than four or five stories. These communities may have less open space at ground level, but with a little imagination, greenery, cafes and shops can all be accommodated in truly exciting ways. "In Vienna," said Jack Diamond in his Canadian Urban Institute address, "the land has a greater mix of uses and there is a high level of social integration. This urban form also supports small-scale retail enterprises."
Thus, these neighbourhoods are economically as well as socially vibrant. This vibrancy, when meshed with ecological health, is the essence of the ecological imagination.
A city of high-rises, which to us seems so modern, was actually first imagined and sketched by the architect and city planner Le Co back in the early 1920s. One of his sketches shows a wall of 50-storey buildings with a tiny biplane flying across their facades. This image reminds us that, like the biplane, high-rises are quaintly out-of-date. It's time for us to experiment with imaginative forms of development that are socially, economically and ecologically more responsible than an architect's grandiose fantasies from long ago.
Edmund P. Fowler, who does not live in a high rise, taught local government, urban studies and environmental philosophy at York University. His books include Building Cities That Work and Cities, Culture, and Granite.
Canada Mortgage and Housing Corporation offers a wealth of information including case studies in residential intensification at www.cmhc-schl.gc.ca/en/inpr/su
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