In October 1973, when it was first occupied, the LBJ Apartments public housing complex in Cambridge was efficient and cost-effective.
But the five- and 12-story high-rise building – made of cast concrete with an electric heating system – has gone through few substantial renovations in the past 37 and a half years, and is in desperate need of repair.
With the help of a $10 million grant from the American Recovery and Reinvestment Act, the Cambridge Housing Authority (CHA) is committed to a “transformative change” in the approach to energy use at the public housing development for senior and disabled residents.
At Skanska, we are working with CHA to make the LBJ Apartments complex one of the greenest buildings in Cambridge. The five and 12-story high-rise building – made of cast concrete with an electric heating system – will be retrofitted into a model of energy efficiency.
The LBJ Apartments complex will be home to many cutting-edge green technologies, including the largest solar panel installation in Cambridge. The Skanska project team will install a co-generation system to augment the onsite gas and electricity systems. The old, outdated energy systems will be replaced by a highly efficient gas-fired heating and central cooling system. New high performance window-walls and a complete re-cladding of the building will add an extra layer of insulation.
The project goes beyond reducing electricity usage. The retrofits will also reduce – at a minimum – 15 percent of the building’s current water usage. A rainwater storage system will also retain water for irrigation.
Life-Cycle Costs
New sustainable buildings are increasingly in demand, but energy-efficient retrofits on existing buildings are often more cost effective, less disruptive, and ultimately better for the environment.
Old and inefficient buildings, which make up approximately 80 percent of buildings in Northeast cities, can and should be retrofitted to be more energy efficient – not just for environmental reasons but because it makes sound economic sense.
According to the United States Green Building Council (USGBC), buildings that feature high-performance systems can reduce water usage by 40 percent and cut energy use in half. The resulting reductions in water and energy bills go directly to the bottom line. The USGBC estimates that businesses that “green” their buildings can anticipate an 8 percent to 9 percent decrease in operating costs.
When considering retrofits, we urge our clients to consider the life-cycle costs of a project. The LBJ Apartments building, scheduled for completion next year, will consume 50 percent less energy than it did before the renovations, saving roughly $255,000 in energy costs per year. This will reduce CHA’s carbon footprint by 2.5 million pounds a year.
Projects like this demonstrate that green retrofits are good for the environment – and the wallet.
Paul Hewins is general manager and executive vice president for Skanska USA’S New England region.
