ENERGY EFFICIENCY The Learning Center It depends. If designed and filled properly, foam filling may slightly improve the thermal efficiency of vinyl frames. Since window frame represents a small percentage of the overall window surface area, the question becomes is the added cost effective. Generally, it will be difficult to recoup the additional investment with the minimal improvement properly manufactured foam filled frames will have on the window’s overall thermal performance. However, if improperly designed and filled, it will have no real impact. Foam filling of the right material, with the right application equipment, in the right areas of the window frames, requires a diligent quality program that is strictly followed. This is difficult to do on a consistent basis in a typical manufacturing operation. However, if a vinyl window is designed with enough hollow cavities, the air spaces can be just as effective as a foam filled product. When evaluating a window’s performance, don’t get caught up in trying to evaluate these kinds of details which may or may not have any real impact. The only way to evaluate the energy performance of a window is to look at it as a system. This is exactly what the NFRC testing and evaluation process does. It looks at the window as a whole, with all of the components interacting together. 12. Will foam filling of hollow frames improve the energy efficiency of vinyl windows? < back to list of questions about energy efficiency 3245 Miracle Drive Murrysville, PA 15668 724-387-2991 PA Contractor ID PA001856