Historic Windows and New Views: Energy Performance and Economic Concerns Affecting the Preservation of Historic Wood Sash Windows

Abstract

New approaches regarding the economics and energy performance of replacement windows are affecting the fate of wood sash windows in historic properties. Recently, the APVA Preservation Virginia added historic wood windows to their 11 Most Endangered List, because of some disturbing trends in window replacement. The current vogue for replacement is driven by both economics and energy performance. Many believe the only solution is purchasing new windows. While replacement window manufacturers and dealers often tout their products as inexpensive and more energy efficient, in actuality original or historic windows can perform to the same standards. Cost analysis suggests that costs associated with replacement options compare to the costs associated with maintenance and repair of original windows. This project confronts the current issues of economics and energy performance, which are driving decisions to replace instead of preserve historic windows. This study demonstrates that historic windows can be maintained and upgraded to energy performance standards and still be economical. The goal of this project is to provide guidance for homeowners, project leaders, and government agencies, in terms of the decision making process regarding the treatment of historic windows.