Investing in an Older Building? PART ONE - ENERGY SAVINGS

Textile Mill Renovation in Mebane

So, you love the walkability of downtown and the scale of the buildings and sense of community, or maybe you are intrigued by the beautiful masonry mills that dot the waterways of the County, or the old production barns that mark the landscape.  

Maybe you want to be a part of shaping a new chapter in North Carolina development that includes the telling of a more inclusive history or gives grounding to the wide-flung visions of future community achievements . Why not take a look at Adaptive Reuse?  The existing buildings that populate our cities and rural landscapes are looking for new life and there are many solid reasons for supporting their renovation and renewal.

Through this series of blog posts, we'll take a look at some of the benefits and challenges of working with visible and invisible  historic fabric of our communities.  But as always, if you have questions about areas we don't discuss, feel free to reach out to us and we'll do our best to provide an answer or coordinate an answer with the other great organizations around us. 

ENERGY BENEFITS

Buildings account for a huge percentage of our country’s energy usage (roughly 40% according to the US Energy Information Administration).  And Construction activity accounts for roughly 60% of our landfill waste.  Reuse of existing buildings helps reduce our energy footprint and has a lower environmental impact than new construction.  According to the Green Lab study from the National Trust for Historic Places:

“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.”   
Additionally, according to a previously published EPA report, that new, energy-efficient building  described above would still take about 65 years to recover the energy lost in demolishing a comparable existing building.  
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These numbers are driven by the destruction of the “embodied energy” in existing buildings.  Through demolition, the builder looses all of the energy that went into the original construction AND is expending additional energy powering equipment for demolition and trucking the debris to a landfill.  On top of those two expenditures, the builder then needs to use additional energy to build the new building on the old site.  Additionally, the demolition increases air particulates and pollutants and can result in harmful exposure to toxic chemicals. 

Although older buildings are not as efficient as newer buildings in their envelope design and in their heating and cooling systems, they do have many characteristics that rely on passive energy solutions.  Most commercial, downtown core buildings, and many residential structures, and ​

agricultural structures relied on the passive circulation and natural ventilation of their spaces.  These historic buildings create a natural circulation through vertical stratification of cold and warm air within the building, using tall ceilings, open stairs, operable windows, and proportions to direct air up and out.   
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Many historic buildings also relied on daylighting rather than electrical lighting.  Tall windows and large span spaces brought in lighting for daily tasks from early morning to early evening.  Daylighting not only reduces the demand on electric lighting, but it also creates a positive environment for working and collaboration that increases efficiency and occupant health.  Several studies have been conducted over the years that quantify the positive effects of daylighting on interior work, including the work of the Department of Design and Environmental Analysis at Cornell University, the Herschong Mahone Group, John Bergs, and Tove Fjeld and Charite Bonnevie.

Lastly, many historic buildings have thick masonry walls, that help modify temperature extremes.  These wall absorb the hot sun during the day and re-radiate it in the cooler temperatures of the evening.

These passive strategies can be paired with newer renewable energy sources such as solar PV panels, ERV systems, occupancy sensors, LED technology, and demand-based energy usage to meet our adjusting demands for community energy efficiency.