October 27, 2013

HENRIE: Constructing Truly Sustainable Buildings

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Greetings Cornell.  It’s been a while.  I was sifting through my thoughts, trying to find something to write about, when I looked up while walking through the Physical Sciences Building.  That building is beautiful, and quite impressive, but I can never shake the feeling there, and various other places around campus, that it’s all a little much.

What do I mean?  Well, I’m thinking mainly about all of the glass and plastic and metal that went into a place like the Physical Science Building. I know that it earned LEED Gold, and is considered energy efficient. This matters a great deal in the long term, but I suspect that the building could have lower embodied energy — the energy employed to create the materials and construct the building — if more “natural” materials were used.

I had a similar feeling when I saw pictures of the planned Tech Campus in New York City: beautiful,  ambitious, but so much embodied energy.  I suppose my preference for wood and earth over soaring, shining confections of metal and glass is a sort of anachronistic idealism on my part; I see at least as much, if not more, virtue in a well-made cottage as I do in a skyscraper. Obviously, I cannot expect everyone to share this feeling, but I do think there are more practical reasons for preferring a cottage. When I look at a skyscraper, while I am impressed, all I can think about is the mines, the furnaces smelting, the glassworks and the cement makers. And, though most of us often forget about it, the only reason the Western world can afford to have so much metal and glass is because it was, and is, being taken from developing nations.  However, there are plenty of local, natural, alternative materials out there just waiting to be used.

Let’s talk about thatch, for instance. Thatch is, for those of you who are unaware, any roofing made from plant material — generally straw or reeds in temperate areas.  It’s definitely a roofing material of a past age in most people’s eyes, but I think it’s delightful. The best thatch is made from reeds of the genus Phragmites, which is an invasive in upstate New York, and commonly grows in the run-off ponds near highways and parking lots. The reeds are cut in the winter when the previous years growth is standing dormant and dead. Well made reed thatch can last decades.  It can certainly equal the 30 years or so that more “conventional” metal or asphalt roofs last. There are various ways to improve the longevity of thatch, such as running copper wire along the top of the roof. which will leach through the reeds destroying fungal spores.  The main concern with thatch is fire, but a thin flame retardant ceiling under the thatch massively reduces that risk.  Thatch is a low carbon, locally sourced, beautiful roofing material.

Now, I am not suggesting that all of Cornell’s buildings be thatched. That would, obviously, be absurd. First off, a thatch roof must be have at least a 50-degree pitch to shed snow properly. Additionally, it’s very expensive due to the highly skilled labor involved (thatching is actually quite difficult, and is not a common skill). But maybe on one or two roofs — perhaps ones that need to be replaced anyway?

What about using earth?  A very cheap building material is dug out of every construction site, and could easily be put to use. Buildings made of rammed earth, clay mixed with straw; these are cheap and highly energy efficient due to earth’s thermal mass.  They are also surprisingly useful even in wet environments like Ithaca. In England, where it rains a fair bit, many traditional cottages are made of a mixture of clay, sand and straw, and many of these buildings stand hundreds of years with a lime whitewash. Earth can be shaped into quite impressive shapes and sizes.  In the Middle East, ten story high rises, vast walls and massive arches have been constructed of packed earth or adobe.  Some such buildings still exist, and are still inhabited. I think it would be a sustainable and very ambitious project if, the next time a new building is built on this campus, it was made of earth, not of glass.

I’m not saying that there is no place in the world for grand, burnished buildings because there certainly is. Such buildings are effective at creating a sense of wonder, but I think natural materials create another sort of wonder.   I simply feel that it would be good for our health, good for our minds and good for the world if a “sustainable campus” were to contain a little less polished metal and a little more dirt.