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Environmental Factors

The evolution of building construction practices throughout the twentieth century has left a spectrum of good and bad practices that architects, engineers, contractors, planners, civic officials, and property owners must recognize to facilitate their efforts to achieve sustainability. Changes in architectural building technologies, particularly in the period after World War II, led to dramatic shifts in how buildings were designed, built, and operated. The nascent passive solar energy movement coupled with the two energy crises of the 1970s that prompted dramatic energy cost increases and heightened concerns over energy security led to a different way to view building performance. Building designers seemed to take note of these lessons and began to design more energy-efficient buildings. Fuel prices and availability stabilized in the 1980s yet still remain high compared with those of the pre-crisis period. However, uncertainty in fuel cost escalation creates growing concerns over energy security and the long-term sustainability of buildings. The numerous energy retrofits completed in the 1980s revealed that there were many alternative solutions to reducing energy use, some of which translate directly from constructing new buildings to retrofitting existing ones. The techniques that translated well included upgrading operational and control aspects of mechanical, electrical, plumbing, and lighting systems with more energy-efficient replacement products or control overlays programmed to use less energy. Modifications to the building envelope that emulated new building construction led to adding insulation to walls and roofs and infilling windows with insulated panels or replacing them altogether. Unfortunately, in certain instances the cost of removing preexisting envelope components, such as windows, made the proposed strategy cost-prohibitive. Decision makers started paying greater attention to energy payback periods and specifically kept first costs to a minimum and focused on recovering the cost of more incrementally expensive design alternatives through the

R.A. Young, Stewardship of the Built Environment: Sustainability, Preservation, and Reuse, Metropolitan Planning + Design, DOI 10.5822/978-1-61091-236-5_3, © 2012 Island Press

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80  Stewardship of the Built Environment

expected energy savings alone. These analysis methods have since been supplemented and even surpassed through the use of life cycle analysis software and databases. At this same time, design professionals began to recognize the inherent sustainability present in many of the features common to buildings built before the mid-1950s. Initial attempts to conserve energy by infilling windows with materials designed to resist heat loss often resulted in higher electrical lighting costs because they blocked daylight. Studies began to reveal that the longforgotten or overlooked strategies of using thermal mass to moderate temperature swings or taking advantage of natural ventilation could play an important role in energy per