Canadian Consulting Engineer
Comment: Green design is no easy streetBuildings Environmental Building Mechanical & Electrical (HVAC) Systems Building Structure Environment
At the Canada Green Building Council conference in Toronto on June 4, I caught a few minutes with Ray Cole. He is one of the sages in the green building movement in Canada and now director of the Centre for Sustainable Research at UBC. Twenty...
At the Canada Green Building Council conference in Toronto on June 4, I caught a few minutes with Ray Cole. He is one of the sages in the green building movement in Canada and now director of the Centre for Sustainable Research at UBC. Twenty years ago when I was an editor on Canadian Architect we asked him to write an article comparing the environmental impacts of different building materials. What were we thinking? It was very early days in the green building movement and we had no idea how complex a question we had asked. Dr. Cole and David Rousseau, then with the Environmental Research Group at UBC, wrestled with the issues and compiled a table of common building materials under headings like energy range, major non-energy impacts, re-use, recycle energy, conversion rates, etc. Nor had we thought through the serious business impacts on the supply industry of an article declaring that one material (say, steel) was more benign than another (say, concrete). Anyway we blithely went ahead and published in March 1991.
In the intervening years sustainable design has become even more complex. A topic at the CaGBC conference was LEED v4 and how the building rating system now includes Environmental and Health Product Declarations (EPDs and HPDs). Sounds like a great idea. But according to one LEED professional, the declarations are highly technical and involved. And for manufacturers it will be costly to certify their products ($10,000 by one estimate), so that smaller entrepreneurs with new inventions could be shut out of the market.
Then there are energy codes and models to contend with. In a panel on this topic, Andre Legault explained how a range of codes could apply to a project, from the (now outdated) Model National Energy Code, to ASHRAE 90.1-2010, to special codes adopted by cities like Vancouver and Toronto. Then you have to decide between compliance paths: trade-off, prescriptive or energy modelling. Jason Manikel of Halsall Associates said that designers of a building project in Toronto might end up having to create five different energy models. Perhaps we shouldn’t complain. All this work requires a legion of engineers.
Is the effort worth it? Yes, of course. Listening to a speaker like Craig Applegath of DIALOG at the conference was a much needed jolt to remind us of what’s at stake. Applegath told of the litany of problems threatening the planet, with greenhouse gases and climate change just one. Deforestation, soil depletion, aquifer depletion, toxic contamination, urban sprawl and species extinction, are all a by-product of humanity’s burgeoning numbers and voracious appetites. We now need 1.4 Earths to survive, he said. We are a “species of pathological parasites,” (he was a biologist before going into architecture), “and we only have one host.”
But Applegath also has hope, citing “symbiotic cities” that integrate ecosystems, “infinite” material and water recycling, and thorium as a fuel.
Ultimately, though, it all comes down to economics. As Applegath said, to effect true change we have to figure out a way to monetize the long term effects of ecological damage in the accounting for any development. And here comes that complexity issue again — establishing an economic value for the environment is the hardest goal to achieve, and for it we need consensus around the planet. Bronwen Parsons