Historic Preservation is the Original Green Building

As sustainability becomes a critical part of architecture, design and construction, a greater focus on thoughtful historic preservation of existing buildings makes common sense.

LEED for existing buildings: operations and maintenance (or LEED EB O&M) certification is perhaps the most energy efficient of all LEED certifications because improving an existing building is the greenest building approach there is.

Simple steps may be taken across the spectrum of LEED credits and prerequisites to achieve historic preservation and sustainability at the same time.

Sustainable Sites:
To reduce heat island effects of asphalt parking lots, plant trees and use pervious surfaces such as stone (pebbles) or crushed shells, which are often found in historic homes. This reduces stormwater runoff which, in a heavy rain, may otherwise fail to be absorbed in the Earth when using impervious surfaces such as asphalt, and overwhelming of sewer systems.

Water Efficiency:
Greywater systems provide opportunities for recycling rainwater and greywater (water from sinks and showers, etc) and reusing it for irrigation or other uses such as flushing toilets and urinals. When combined with new low flush/no flush (waterless) urinals and toilet technologies, the amount of water consumed can be significantly reduced.

Energy and Atmosphere:
Achieving minimum energy performance (a LEED Prerequisite) can often be accomplished using very traditional architectural design details that are consistent with historic preservation. In some geographic areas, older buildings may have dense ivy growth which can be a natural source of shade and insulation for a building.

Shade and fresh air can also be created using classic features such as shutters, awnings and operable double hung windows which are common in historic structures. Planting trees is also an excellent source of shade.

EA Prereq 2 may be easier to achieve with up to a 70% reduction in electricity usage that can result from relamping a building (replacing incandescent bulbs with compact fluorescent lamps). To further insulate historic structures (and further reduce heat island effects as mentioned above), which reduces AC demand in summer and heat loss in winter, a green roof may be used. When considering a green roof for a historic structure, remember that your local historical society may require it to be hidden from the street to preserve the appearance of the building.

Materials and Resources:
Companies such as Great Forest may be hired to develop a whole building approach to managing a construction waste management process as well as intricate and thoughtful recycling programs. Such companies can be very helpful in solving any problems that may exist in order to comply with LEED for Existing Buildings: Operations and Maintenance MR Prereq 1 and MR Prereq 2, (sustainable purchasing policy and solid waste management policy), respectively.

The aforementioned relamping should be addressed while making sure that low mercury levels (in picograms) are present in any compact fluorescent lighting. MR Credit 4 (as well as MR Credit 4.1 and MR Credit 4.2) require that mercury in lighting not go beyond certain levels.

Indoor Environmental Quality:
The simplest way to improve/ensure indoor environmental quality is to make your building smoke free and make sure operable windows are still operable (i.e. not painted shut). In Manhattan, many former factory buildings that are now used as lofts for offices, etc... have excellent light because of their tall, wide, operable windows. In such buildings with large windows, daylighting technologies should be considered to reduce electricity consumption for additional lighting when lumens levels are acceptable due to natural light alone.