This January 1st was the official start of a new city-wide resolution – we will all be bringing our own bags to the store. This step forward in increasing awareness of what we are throwing away makes me think back to a talk given by my favorite preservation economist (what, you don’t have a favorite?). In our 2015 “Mightier Than a Wrecking Ball” conference Donovan Rypkema stated the following:
“Every time a little 2200 sf house…would have been rehabilitated instead of raized…that would have more environmental impact…then all of the plastic bags that 440 people would have used in their lifetime.”
Does this ring true here in Salem? We certainly understand that demolishing a house means that the volume of materials will end up in the landfill (with some recycled, hopefully). A demolished 2,200 sf house (with cellar and attic space) will become 297 cubic feet, or 7.4 construction dumpsters of landfill. (source) That is the same as me generating household trash for 354 years. (calculator)
What goes into the dumpster, in addition to volume, is the energy used to make those materials (called embodied energy).* Fuel once used to mine, harvest, manufacture, ship and install are all wasted when a building is demolished. Then there is the intensive energy needed to build a new house. Rypkema also highlighted a study that showed:
To build a new home on a clear site uses 182 tons of material energy (this includes energy used to extract, create, ship and discard the materials) and to demo an old house, haul it to a landfill and rebuild with LEED gold architecture standards used twice as much material energy - 351 tons. However to rehab a historic house uses only 47 tons of material energy. Seven times less than
or our community, which obviously values sustainability and resiliency, it makes a lot of sense to continue and celebrate the tradition of re-using our historic buildings. Certainly, a vibrant city will always be changing and that means some buildings will be replaced over time. When evaluating the need for demolition we are often weighing the social, historical or cultural value of a building against the financial goals and community need delivered by the developer. It will serve our community well to also include the quantifiable environmental impacts of “recycling” (reusing) old buildings in the equation.
Now that we have implemented a plastic bag ordinance, mandatory recycling, and solar rooftop programs, etc. the city can continue to advance environmental concerns by insisting that new buildings are built to last (quality design, quality construction); that we continue to repurpose existing buildings; and that we maintain the buildings we have, extending their lives into the next century.
*If we are going to be fair many homes in Salem were built before fossil fuels began to be used in earnest. While some materials in my 1850s house were shipped or processed using coal power much of the mining, harvesting, manufacturing and site delivery was done with hydro, livestock or man power. Historic houses were LEED certifiable before it was cool! That said, throwing away dumpsters full of heavy-labored and hand-crafted building materials that depleted forests shouldn’t make anyone feel warm and fuzzy.