Report shows value of building reuse, retrofitting

January 26, 2012

A new report by the Preservation Green Lab entitled "The Greenest Building: Quantifying the Environmental Value of Building Reuse" outlines how retrofitting and reusing buildings may offer environmental savings over taking down old structures and rebuilding them.

According to the report, little had been known about the climate change reductions that might be offered by reusing and retrofitting existing buildings rather than demolishing and replacing them. However, the new data is suggestive of how one practice is more efficient than the other.

"Moreover, it can take between 10 and 80 years for a new, energy-efficient building to overcome, through more efficient operations, the negative climate change impacts that were created during the construction process," the report outlined. "However, care must be taken in the selection of construction materials in order to minimize environmental impacts; the benefits of reuse can be reduced or negated based on the type and quantity of materials selected for a reuse project."

The study found that although the range of environmental savings from reuse varies widely, based on building type, location, and assumed level of energy efficiency.

These savings from reuse are between 4 and 46 percent over new construction when comparing buildings with the same energy performance level.

Despite the seemingly small difference in the savings when comparing the two methods, the study suggests that the absolute carbon-related impact reductions can be substantial when these results are scaled across the building stock of a city.

The study cited an example, Portland, Oregon. If the city "were to retrofit and reuse the single-family homes and commercial office buildings that it is otherwise likely to demolish over the next 10 years, the potential impact reduction would total approximately 231,000 metric tons of CO2 – approximately 15 percent of their county’s total CO2 reduction targets over the next decade."

According to the National Trust For Historic Preservation, the findings suggested that retrofitting older buildings may be the best path forward for cities across the country.

Retrofitting is one of the areas of focus for the Greater Philadelphia Innovation Cluster for Energy Efficient Buildings (GPIC), the Department of Energy-designated innovation HUB for the development and design of energy efficient buildings and technology.

The GPIC is located at the historic Philadelphia Navy Yard, where a consortium of organizations from the private sector, academia, energy development and the government are working to lower the country's energy consumption through buildings.