Saturday, December 29, 2012
Does LEED Lie?
I wrote in the comments,
We can debate the degree to which LEED “lies,” but there is no doubt it can be deceptive. That’s because it uses an additive point system. Add enough bike racks, solar panels, etc. and you can get a LEED Platinum building for something that in reality is not sustainable.
In the case of these glass buildings, there are two major problems. First, the glass is engineered to keep out ultraviolet light, keep heat gain down, have some insulation value, etc. The muti-layer window that results is sophisticated but requires a large amount of embodied energy to produce it. And to add insult to injury, the chemicals wear out over time, so the glass will all have to be replaced after an unknown period (unknown because the current experiments are still early in their life cycle). That’s more wasted energy. The best walls have a high R value, low embedded energy and are like the Energizer Bunny – they last, and last, and last.