Historic preservation is inherently a sustainable practice.
A commonly quoted phrase, “the greenest building is the one that’s already built,” succinctly expresses the relationship between preservation and sustainability. The repair and retrofitting of existing and historic buildings is considered by many to be the ultimate recycling project, and focusing on historic buildings has added benefits for the larger community.
Traditional materials are generally durable, the continued maintenance of historic buildings and features relies on local craftsmen rather than replacement parts, and these structures generally make up the heart of our towns and cities. For decades, preservation programs like the Historic Preservation Tax Incentives have demonstrated that whole communities can be revitalized by rehabilitating individual buildings.
According to the U.S. Energy Information Administration, buildings are the largest consumers of energy in the nation. In recognition of the role the built environment plays in energy use, Technical Preservation Services develops guidance and technical information about how historic properties can incorporate sustainable practices to reduce energy consumption, while maintaining those characteristics that make historic properties significant.
- Weatherizing Historic Buildings
- Solar Panels on Historic Buildings
- Green Roofs on Historic Buildings
Historic buildings can be energy efficient. Per square foot, historic commercial properties rank among the best in terms of energy consumption. However, there is always room to improve a building’s energy performance.
Weatherizing or otherwise improving the energy efficiency of historic buildings should be undertaken carefully to preserve a building’s historic character. Because energy retrofitting is continuously evolving, products or solutions that are popular today may fall out of favor in the future. So it is important to select products and treatments that are reversible and do not require major structural or material changes.
Rehabilitating historic properties often involves introducing new systems or features to meet contemporary needs. These changes can usually be made in ways that are sympathetic to the existing structure and site. In order to accomplish a sensitive alteration, new features should be both compatible with the historic property and reversible.
Adding solar panels to historic properties can have a significant impact on the character and visual qualities that covey a property’s cultural significance. Solar panel installations should not become prominent new elements that detract from the character-defining features of a building or landscape. To assist property owners, historic preservation commissions, and policy makers, we have developed information to assist in applying the Standards for Rehabilitation to the installation of Solar Panels on Historic Buildings. Additional guidance is available in ITS 52: Incorporating Solar Panels in a Rehabilitation Project which provides examples of compatible and incompatible installations of solar panels on historic buildings.
Flat or low-slope roofs provide excellent opportunities to introduce a contemporary feature in a rehabilitation project, such as a green roof. When planning to add a green or vegetated roof, structural capacity, visibility, and future maintenance must be considered before installation. For more information, refer to Green Roofs on Historic Buildings and ITS 54: Installing Green Roofs on Historic Buildings.
Last updated: October 24, 2022