I’m trying to wrap my mind around this concept of embodied carbon footprint. In other words, we’re looking at how much energy was consumed in the mining, manufacture and transportation of the materials in a home. Carbon footprint is the measure of the carbon dioxide released by the energy used to manufacture and transport something.
At the Greenbuild International Conference & Expo, two representatives of an architectural firm presented their carbon footprint analysis of 10 homes built by the firm.
They talked about one project that had a low carbon footprint for the relative size of the house because of the way it was built. One carbon-saving tactic was the re-use of concrete roof tiles from the house that was previously on the site.
I applaud their use of the reclaimed roof tiles. The carbon embodied in those concrete tiles – one of the most carbon-intensive building products – would continue to serve a purpose. They attributed a carbon footprint of zero to the project for those tiles.
I understand that the project side-stepped the carbon footprint of new tiles by using the old ones. But the new tiles that would have otherwise been installed were already manufactured. There were skids of new tiles sitting at some warehouse waiting on a project. The carbon footprint was set.
When that new tile is bought for a project, the warehouse will order more. But what if it’s not used? Say it sits there for two years, then the warehouse trucks it to a landfill because it didn’t sell. That carbon surely went to waste then. But the energy to make the tiles was consumed regardless of its final destination. The manufacturer continues to churn out batches of tile, consuming energy and expending carbon dioxide.
How far back up the supply chain do we have to go to have a real impact? Is it enough to simply reduce the carbon footprint on a particular project? Will manufacturers stop making high-carbon products, or will builder and architects stop specifying them? Or is simply not using the products in our project enough?
To me it’s like the person who refuses to fly in a commercial airliner because of the carbon footprint. The jet is flying whether you’re on it or not. But your personal carbon footprint is smaller, although the global impact is unaffected.
What do you think? How much can we do about carbon footprint in our building projects? What else do you do to minimize your carbon footprint?
Gary Wollenhaupt is an experienced writer and editor, with a background as a daily newspaper reporter as well as corporate and agency public relations and marketing. He is constantly looking for affordable green upgrades to make to his home in eastern Kentucky.