Rigid PVC Window Profile

Vinyl window frames are manufactured from rigid polyvinyl chloride, sometimes referred to as uPVC (unplasticized polyvinyl chloride). They typically contain a number of air pockets to reduce thermal conductivity/increase the R-value. These air pockets can optionally be filled with foam insulation to further increase the R-value. The sources reviewed did not always disclose what type of foam is used, but some explicitly mentioned polystyrene and polyurethane foams. 

Vinyl window frames can be used for many different styles of windows such as double-hung, single-hung, awning, fixed, sliding, and casement. They are not typically painted, but are available in a wide range of colors. Darker colors may require additional UV stabilizers since they use less titanium dioxide, which functions as both a white pigment and UV stabilizer. In addition to UV stabilizers, PVC requires heat stabilizers in order to prevent the polymer from degrading when subjected to high temperatures during the manufacturing process. In the U.S. these are commonly organotin or calcium and zinc compounds. According to the vinyl industry lead- and cadmium-based stabilizers are no longer used in rigid vinyl in the U.S. Lead-based stabilizers are, however, still marketed for use in PVC window profiles outside of the U.S. 

This Common Product covers the composition of the vinyl window frame and sash. It excludes excludes other window components that may be used with all types of frames such as glass pane(s), films, sealant, seals, spacers, gas fill, and hardware. For an example of common materials that can be used in an insulating glass unit (IGU) see the Double Pane IGU Common Product.