What is the "U" value of the FCM-4646?A. The Velux FCM-4646 has a U value of .60
I just purchased 28 impact glass skylights from you and would like to apply a reflective tinting to them. Can it be done and is there a limit to the tint and R value of the product?A. Tinting the Velux FCM-4646 will void the warranty, will not help with heat and will ruin the quality of the product. It is not recommended to use tint on windows, a shade should be considered.