An engineering and economic analysis of energy loss through single paned windows in a large college building is presented. The goal of this work was to determine an economically viable solution for Marietta College to save on energy costs. Based on the model presented, the economics of double paned window installation are investigated. An alternative solution employing the addition of storm windows to the existing single paned windows has yielded very exciting results. While double paned windows are generally the first thought when it comes to energy efficient windows, this work shows that storm window addition yields a much lower investment and quicker payback period for this specific building. The engineering analysis and experimental technique presented can be used to investigate the cost benefit of single paned window upgrades for other buildings.