VELUX FCM fixed curb mount skylights are ideal for replacing existing curb mount skylights, including old plastic bubble skylights. It can be installed on a flat roof at 0° up to a 60° roof pitch on a site-built curb. VELUX skylights are an energy-efficient way to bring sunlight into a home and make dark rooms come to life, all while maintaining privacy. Installing a skylight is one of the most impactful ways to enhance the brightness and beauty of a room. FCM 2246 models are Designed to fit a site-built curb (not included) with outside dimensions 25-1/2 in. x 49-1/2 in. Qualifies for a 10-year "No Leak" installation warranty when installed with ECL 2246 flashing on a shingle roof with a pitch between 10° and 60° or ECW 2246 flashing on a tile roof with a pitch between 14° and 60° (flashing kits are sold separately) Features tempered, Low-E3, argon-filled, double paned glass, which is recommended for in-reach applications Please note: VELUX recommends and most building codes require laminated glass for out of reach applications Click below to view and purchase compatible VELUX flashing models