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Preservation is inherently sustainable

Last week I had the pleasure of hearing Barbara Campagna speak at Victoria City Hall. Her presentation was part of a Transformational Lecture Series sponsored by the Cascadia Region Green Building Council.

Barbara Campagna is the Chief Architect of the National Trust, which administers a Sustainability Program to ensure that the “29 historic sites of the National Trust are integrating historic preservation values with green building practices – from green housekeeping techniques to sustainability master plans to LEED certification for historic rehabilitations.” (source) As the lecture description also noted:

The National Trust for Historic Preservation’s Sustainability Program is demonstrating that conservation and improvement of our existing built resources, including re-use of historic and older buildings, greening the existing building stock, and reinvestment in older and historic communities, is crucial to combating climate change.  The construction and operation of buildings accounts for more than 40% of the United State’s carbon dioxide emissions. But reusing and retrofitting our existing buildings can reduce these emissions dramatically. In fact, our existing buildings are one of our greatest renewable resources.

Campagna’s informative presentation made the case eloquently that preservation is inherently sustainable. Preservation means that you:

  • reuse existing buildings
  • reinvest in communities (making existing communities and the city core attractive and amenity-rich counters sprawl)
  • retrofit older buildings
  • respect historic integrity

It turns out that buildings built before 1920 and after 2000 are the greenest in terms of low energy use: they have venting windows, and they’re adaptable (office to condo and vice versa). The worst buildings are those built in the 1970s, 80s, and 90s: difficult to adapt to any kind of reuse, inflexible HVAC systems (no individual control over venting, for example), high-energy usage. Quality of materials also comes into play: buildings from before 1920 and after 2000 are better quality. All of this suggests that in the post-World War II decades we went on a bender – of building cheap (not to last) and also of building mono-culture buildings. (For example, Robert Stern points out that modern office buildings can only be good for being office buildings: their huge floor plates mean that the distance from exterior wall – where there are [non-venting] windows that let natural light in – to the core [center] of the building is too far to allow carving the space into discrete rooms. The only thing these buildings are good for is an open plan cubicle farm – and even then, you need electricity to bring light to most areas. To retrofit a building like that so as to allow reshaping it into either smaller offices or even living spaces would involve carving a light-well into its center – a huge and costly retrofit, as we’re seeing here in Victoria with the retrofitting of the old Hudson’s Bay Department store into condominiums.)

Campagna also spoke about life-cycle assessment, which (if I understood her correctly) is a significantly better metric than embodied energy for assessing eco- or “green” questions when dealing with preservation. If I understood her point, much of what’s applied to preservation comes from a 1981 study on embodied energy – and it turns out the data is suspect.

The City of Victoria likes to congratulate itself on its work with historic preservation, and one of Victoria Council’s most outspoken defenders of built heritage, Councilor Pamela Madoff, was at Campagna’s presentation.

However, sadly Councilor Madoff also voted in favor of tearing down Victoria’s storied Johnson Street Bridge and replacing it with a new structure. One wonders whether Campagna’s illustrations of preservation and sustainability provoked any kind of reconsideration of Victoria’s unique historic bridge, or whether Industrial Archeology is simply too far a stretch for just a building preservationist.

Another thing to note: one of the arguments that the City of Victoria’s Engineers made – an argument subsequently embraced by some of the councilors who profess Green allegiances, notably Councilor Sonya Chandler – is that building a new bridge represents less embodied energy than refurbishing (preserving) the old one. Yet as Campagna’s lecture suggested, the embodied energy argument has to be pondered carefully. Surely, manufacturing new steel in China (after burning bunker oil to transport the raw materials from South America, say, to China’s factories), then burning more bunker oil to transport that steel to Victoria, is not the greener option. And let’s not even get started on how much fresh concrete a new bridge will require.

There was an irony in seeing a councilor who’s a heritage advocate listen attentively to an expert historic preservationist make the argument that the embodied energy argument should be viewed with skepticism, that preservation and reuse are always the greener options, and that retrofitting old buildings – can we say old structures? – is the environmentally responsible thing to do, given her readiness to trash the Johnson Street Bridge.

The question is: will Campagna’s message reach Victoria on the issue of the Johnson Street Bridge, or will Victoria remain comfortable in believing that it’s doing its best with regard to preservation …and sustainability?

1 Comment

  1. […] (reposted from Yule Heibel’s Post Studio, March 16 2010) […]

    Pingback by Johnson Street Bridge, Victoria BC — March 17, 2010 #

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