What’s old is new (and green)
Trends in sustainable construction are ever evolving as new technologies and more sustainable building materials are continuously being tested and introduced into the market. However, one of the biggest evolutions in sustainable construction has nothing to do with cutting edge technology. Rather it is the re-emphasis on that fact that the greenest buildings can be the ones that are already built. Buildings from prior generations don’t suffer from the planned obsolescence that we have engineered into modern consumer products.
There is a wealth of literature explaining the merits of new sustainable construction – less impact on the environment, lower energy and maintenance costs, healthier environment for tenants. However, more recent studies have proven that green retrofits of existing buildings have less long-term environmental impact than the demolition and new construction of a green building on the site, while offering the same benefits as new construction.
For full disclosure, renovations of existing buildings rarely create the highest performing buildings. But it is important to remember that we are not talking about creating the highest-performing building possible utilizing the most cutting edge technology and construction practices. The conversation is about the total sustainable footprint and overarching impact to the environment. The improvements to existing buildings, plus the embodied energy already present, make them preferable in the building life cycle.
Consider the amount of energy and materials that go into a new construction project and the amount of time elapsed to overcome the environmental impact. A recent study suggests that it can take a minimum of 10 and as many as 80 years to offset the climate change impacts of the demolition and construction of a new green building, even one that is 30 percent more energy efficient than the building it replaced. This takes into account all of the energy expended to manufacture the building materials, transport those materials to the job site and, of course, the energy used during the actual construction phase.
Building owners and operators are catching on. Within the past few years, green renovation or retrofits have been happening in some very high-profile buildings. The famous Merchandise Mart in Chicago – all 4.2 million square feet of it – was awarded a LEED certification after undergoing a top-to-bottom green retrofit, completed in 2009. And the iconic Empire State Building was awarded a LEED-Gold certification in 2011 after a massive ‘green up’ of the building was completed. Skanska managed to get its floor on the building’s 32nd floor to LEED Platinum. In Portland, an old vacant Meier & Frank department store warehouse built in 1927 was renovated and now serves as the LEED Platinum-certified North American corporate headquarters for the Danish wind company, Vestas.