May 28, 2012

New Urbanists Debate Merits Of Glass Towers

Defenders of highrises say the building form defines Vancouver’s downtown neighbourhoods

Bob Ransford

A significant feature of Vancouver’s urbanism was put on trial recently. One of the godfathers of the New Urbanism movement charged that highrises, especially Vancouver’s ubiquitous glass towers, are a fundamental mistake and an assault against human scale. It wasn’t the first time that neo-traditional architect and urban theorist Leon Krier attacked the form of high-density residential development that defines Vancouver’s inner city. This time, the spirited debate he sparked at the 20th annual meeting of the Congress for the New Urbanism in Florida two weeks ago still wages on in blogs and on Twitter.

New Urbanism appeared on the scene in the late 1980s as a grassroots architectural and urban-design movement that decried auto-dependent sprawl and advocated a return to traditional pre-Second World War compact, walkable neighbourhoods with a mix of housing types and other uses. It continues to evolve and adapt, embracing many of the tenets of smart growth and sustainable development.

I was an early convert to the movement and a longtime member of the Congress. The New Urbanist tent is a big one, bringing together theorists and practising professionals, many with their own interpretation of urbanism — new or old. Needless to say, you put more than two disciples of the movement in a room and you get a debate. Krier provoked this latest one by declaring buildings higher than four or five storeys alienate people from their community, use way too much energy and violate the principles of traditional architecture that speak to human scale.

Krier and a group of followers argue that towers create almost gated-like communities in the sky where residents don’t connect, avoiding interaction and even eye contact as they move up an down their vertical neighbourhood in elevators. Steve Mouzon, a Miami architect who has written a wonderful book on the simple, common sense approaches to achieving sustainable development — The Original Green — tweeted Krier’s speech and went on to reinforce the argument against residential towers like Vancouver’s with an article a few days ago in Better Cities and Towns blog.

He argues that highrise towers are anything but sustainable, especially the glass towers that are so popular in Vancouver, because their curtain wall construction that relies on glazing panels fails to provide thermal mass adequate to retain heat in winter or stop the impact of a hot sun blazing through windows in summer. As peak oil energy costs climb towards the unaffordable, Mouzon believes glass-clad highrises like Vancouver’s will move closer towards being uninhabitable, yet they can’t be adapted to other uses because their square form ensures that deep interior spaces can’t be naturally lit and the higher wind speeds at the top of skyscrapers make it hard to naturally ventilate with opening windows.

On the other side, defenders of highrises, especially Vancouver urbanists, proudly defend a building form that uniquely defines our downtown neighbourhoods. They argue that the livability of Vancouver’s downtown is largely due to and not despite “the Vancouverism” — a form of development that concentrates density in slim towers arranged to protect view corridors and ensure privacy through adequate placement, combined with a podium that addresses an inviting and active street front with townhouses at a scale that relates to pedestrians.

They also argue that the land-use efficiency that is achieved with towers more than offsets any energy-efficiency compromises. Most defenders of the highrise form admit highrises aren’t the only answer to achieving higher densities in an urban setting. Fans of the Vancouverism also argue that not every form of highrise tower works. Former Vancouver planning director Brent Toderian waded into the online debate with a tweet arguing for “density done well.” He claims the key to good urbanism is the right forms and levels of density in the right places, “for the right reasons, relative to context, design and performance.”

The theory of the “Vancouverism” is that the slim point tower, one that usually has a floor plate size no larger than 6,500 square feet — about six to nine suites per floor depending on suite sizes — not only works well as a vertical form that avoids large building masses from dominating the skyline, it also works well at the street level where it can anchor the end of walkable blocks lined with two- or three-storey townhouses that provide “eyes on the street” and a series of actual front doors at the street level.

The debate about whether highrises are an appropriate urban form isn’t a black and white one. I am with many students of urbanism who have concluded that towers have their place, but they aren’t the only answer to density. I also believe it is time for Vancouver to explore other forms of density. Mid-rise buildings in the 10- to 15-storey range are beginning to emerge as the new urban form in the Southeast False Creek area. It will be interesting to see how urban living evolves in this district.

Recent building code changes that allow wood-frame construction for buildings as high as six storeys are likely to soon spur development of this form of density along many of Vancouver’s arterial corridors. While today we argue about whether highrises are good or bad, a few years from now we might be arguing whether mid-rise buildings achieve enough density to make efficient use of land. Bob Ransford is a public affairs consultant with COUNTERPOINT Communications Inc. He is a former real estate developer who specializes in urban land use issues.

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