Full Description

Sales of high-performance triple-pane windows make up only a small fraction (~3%) of total window sales in the United States with relatively stagnant market growth over the past 20 years. High costs have been the most commonly cited barrier to adoption. The emergence of thin triple pane IGUs has the potential to revolutionize the high-performance window market – in particular the retrofit market – by allowing triple pane performance IGUs to fit into the glazing pocket of double-pane window frames and enabling glass-only upgrades for situations where the double pane frames are still in good condition. The retrofit market also has unique challenges not found in new construction that can be solved or reduced by thin triple-pane windows. Insert replacements are often pursued instead of full-frame replacement but this method reduces the net free area of a window and can turn an egress window into one that no longer meets the requirements for egress. Standard triple pane IGUs are both thicker and heavier than doubles which in turn requires thicker insert frames increasing the chance of this problem. In addition to reduced area, the thicker frames required by standard triple pane windows can lead to greater drywall and trim molding modifications, creating higher installation costs. Thin triple pane IGUs which are the same thickness as doubles and only a little more weight can be fitted into new or existing double pane frames and achieve the higher energy performance target of triples while minimizing the chance of causing these retrofit challenges. This paper presents information from a field test experience that highlights the material and labor costs of retrofitting thin triple pane IGUs into existing vinyl frames, the installation experience, the supply chain, purchasability, energy and non-energy performance improvements associated with retrofitting windows with triple pane IGUs that utilize thin glass and krypton gas into standard double pane frames. It also discusses tests and considerations for deciding on whether to pursue an IGU only retrofit versus a window replacement.

Product Details

Published: 2022 Number of Pages: 8 Units of Measure: Dual Product Code(s): DBldgsXV-C043