The adage that is far “greener to preserve a building than build a new one” is bandied around quite a bit – but is it true? Does the value of energy efficient construction materials and technology outweigh the advantages environmental benefits of restoration?
There is no doubt that historic buildings are highly desirable. Building with history and character give a community a sense of place and continuity. In fact, historic areas in most towns and cities across America are generally considered the most sought after neighborhoods to live in or visit. You don’t have to look any further than charming downtown Portsmouth, NH to understand the integrity and importance of preservation. However, does it make environmental sense to keep these old and often energy inefficient buildings?
A new report from Preservation Green Lab of the National Trust for Historic Preservation provides a comprehensive analysis of the potential environmental benefit of building reuse versus new construction. According to Preservation Green Lab the study concludes that, “when comparing buildings of equivalent size and function, building reuse almost always offers environmental savings over demolition and new construction.”
Those findings include:
- Reuse Matters. Building reuse typically offers greater environmental savings than demolition and new construction. It can take between 10 to 80 years for a new energy efficient building to overcome, through efficient operations, the climate change impacts created by its construction. The study finds that the majority of building types in different climates will take between 20-30 years to compensate for the initial carbon impacts from construction.
- Scale Matters. Collectively, building reuse and retrofits substantially reduce climate change impacts. Retrofitting, rather than demolishing and replacing, just 1% of the city of Portland’s office buildings and single family homes over the next ten years would help to meet 15% of their county’s total CO2 reduction targets over the next decade.
- Design Matters. The environmental benefits of reuse are maximized by minimizing the input of new construction materials. Renovation projects that require many new materials can reduce or even negate the benefits of reuse.
- The Bottom Line: Reusing existing buildings is good for the economy, the community and the environment. At a time when our country’s foreclosure and unemployment rates remain high, communities would be wise to reinvest in their existing building stock. Historic rehabilitation has a thirty-two year track record of creating 2 million jobs and generating $90 billion in private investment. Studies show residential rehabilitation creates 50% more jobs than new construction.