May is preservation month the theme of this year is, “Old is the New Green!”. With most people looking for ways to minimize their impact on the environment in their corner of the world it is important to not do anything to a historic building that will damage the historic fabric of the structure.
Historic buildings are “green” because their materials are repairable, durable, and contain embodied energy (energy already expended in construction). Many of these attributes cannot be found in modern “green” solutions.
As part if the National Park Service Technical Preservation Services there is a series of interpretations of The Secretary of the Interior’s Standards for Rehabilitation (http://www.nps.gov/history/hps/tps/tax/ITS/itshome.htm). These are divided into compatible and incompatible treatments with explanations and pictures. If you are going before an historic review board – this is how they will evaluate the changes you want to make.
An interesting article in this section is #54 “Installing Green Roofs on Historic Buildings” – as long as the foliage is not visible from the street scape installing the green roof is acceptable. And somewhat encouraged to enhance the energy-efficiency and sustainability of the building. Interesting thoughts and ideas to join new construction with old buildings in a sensitive manner.