<p xmlns="http://www.w3.org/1999/xhtml">Changes to the forthcoming 2015 International Energy Conservation Code remove the blanket exemption for renovations to historical properties. The new language, approved earlier this month, pertains to buildings designated as historic structures as well as to those listed with local, state, or national registers as a contributing resource within an official historic district, such as Boston's South End (shown).</p>

Changes to the forthcoming 2015 International Energy Conservation Code remove the blanket exemption for renovations to historical properties. The new language, approved earlier this month, pertains to buildings designated as historic structures as well as to those listed with local, state, or national registers as a contributing resource within an official historic district, such as Boston's South End (shown).

Architects now must prove that their historical projects are worthy of exemptions from the International Energy Conservation Code (IECC), following changes to the forthcoming 2015 version approved by the International Code Council earlier this month. The changes were made during the final comment period for Group B codes, which includes the IECC.

Though earlier versions of the IECC exempted historical structures from code compliance on renovation work, the requirements varied depending on which version of the code was enforced in a particular jurisdiction and to what extent the code was enforced. The 2012 version of the IECC, for example, exempts residential and commercial buildings registered with local, state, or national historical registers from compliance on renovations or additions. As of October 2013, only six states had adopted the 2012 code in its entirety, signaling that updates contained in the 2015 version will likely face protracted implementation.

The changes, proposed by a team of industry representatives from the New Buildings Institute (NBI),the Natural Resources Defense Council (NRDC), and the Institute for Market Transformation strip the exemption language from the code. The group added a requirement that project teams file a report with a code official when seeking immunity on specific areas of the design or construction. The changes also include a new definition for residential and commercial historical structures in the definitions section, instead of its previous location in the body of the code.

To be considered a historic structure by the code’s new language, residential or commercial building must be: certified or eligible for listing by state or national historic preservation registers; designated as historic under local or state law; or certified as a contributing resource within a historic district that is listed with the National Register of Historic Places or an equivalent state or local body.

The new language targets missed opportunities in existing code versions to increase old buildings’ energy efficiency, Laurie Kerr, AIA, director of NRDC’s City Energy Project said in an email. “This is not an eccentric issue affecting the occasional Federal mansion or Deco skyscraper,” she wrote. “The impact has had wider reach than one might think. In the nation’s older cities, whole neighborhoods are often landmarked, resulting in a surprisingly large percentage of buildings falling under this umbrella.”

In Boston, for example, more than 8,000 properties are either located in one of the city’s nine Historic Districts or are designated as a local landmark, according to the Boston Landmarks Commission. For Manhattan alone, New York’s Landmarks Preservation Commission lists 65 historic districts; Kerr adds that approximately a quarter of all lots in that borough are landmarked.

“A greater level of care will be required on all of these projects,” says Sean Denniston, a project manager at NBI. “No more assumptions that, ‘Oh, it’s historic, so we’re not going to do anything.’ Now it’s going to require a greater thoughtfulness of what is the impact of doing this on a building. Is it really going to be a problem to comply with this portion of the code?”

Denniston says compliance with IECC 2015 will likely be most challenging when renovations to historical structures require either replacing windows or opening up walls. Much of IECC 2012’s requirements apply to new construction or renovation work and call for such improvements as a continuous air barrier in new residential spaces and in new commercial spaces in all geographic regions but the southeastern U.S.

Still, with the opportunity to seek amnesty for areas of the design in which code compliance could lead to damage or degradation of the structure’s historical character, Kerr writes, “the new approach is balanced, providing protection for historic properties from unforeseen consequences of the code while requiring compliance in the majority of instances where the character of a property is not impacted.”

Photo courtesy Flickr user timsackton via a Creative Commons license. 

Editor's Note: This article has been updated to add the designation of AIA to Laurie Kerr's title.