What are the environmental factors of tall buildings?
(Updated June 2013) At the council meeting on Dec 16, 2010, a council member asked the Planning Department about optimal building heights in terms of environmental factors. The staff response lasted about a minute. Speaking as Director of Planning, Brent Toderian advised our elected officials that the optimal height of a building is sixty storeys. Upon further research, people will realize that the topic is MUCH more complex and deserves a fair discussion. At the time Council requested from Planning Department data comparing energy performance of different building forms. What were they told at the time? An honest discussion is needed. Our elected officials are generally not academically or professionally trained in architecture or land use. They depend heavily on staff statements and advice. But are staff saying the right things to guide our city’s development?
The point we wish to make is that this is a large topic and deserves more public scrutiny, dialogue and debate — especially in a city that seeks to be the greenest in the world by 2020. This page brings together information from various sources, and we welcome further suggestions, to citizenYVR@gmail.com.
For starters, we recommend “Adapting Buildings and Cities for Climate Change–A 21st Century Survival Guide,” by Sue Roaf (Architectural Press, 2009). Chapter 12 is titled “The End of the Age of Tall Buildings.” Download the book in PDF here:
Article in Globe and Mail 19-Apr-2011. (Cracks in the City of Glass, by Frances Bula). Excerpt: “Planners and sustainability experts wring their hands about the lack of energy efficiency – glass, after all, is the poorest insulating building material around.”
Here are some other sources on the environmental implications of tall buildings. There are many more. Proponents of tall buildings may try to dismiss the concerns about environmental impacts.
It would be helpful, for example, to have a complete and independent audit of the ecological footprint and life-cycle impacts of the glass-covered Shangri-La, currently Vancouver’s tallest building.
An architectural expert has written CityHallWatch that the following points are widely accepted and unlikely to be challenged by professionals:
- Glass clad buildings require proportionally the highest level of air conditioning (compared to other buildings) due to heat gain via the greenhouse effect, and therefore have poor energy efficiency.
- Glass cladding has the lowest R rating (insulation level) and thus requires the most heating in winter and therefore demonstrate poor energy efficiency.
- High rise buildings have the highest unit utility cost due to the need to pump water up multiple stories. For example, the energy to pump water up 60 stories for someone to take a simply take shower is enormous.
- Points 1), 2) and 3) together point towards glass clad high rises as the least energy effective building design. In Vancouver glass clad buildings and high rises are largely synonymous (glass cladding is the lowest cost way to clad a building and thus most desirable for developers.)
Anyone observing closely the demolition and construction work for a tall building knows that the environmental impacts can be huge. The City of Vancouver should look at quantifying the impacts — material flows, fossil fuel consumption, creation of waste, traffic, and more. The impacts of building a tall building of concrete, steel, and glass are enormous.
WHAT YOU CAN DO: CityHallWatch encourages you to write your elected officials, call for a sincere and factual discussion about the ecological impacts of various building forms, and then ask the city to amend the building code to address these points before rushing headlong to approve more tall towers and rezone large sections of the City.