Velux have a fantastic selection of skylights for flat roofs. The FCM , VCM and VCS products give you a wide range of options: In fact these skylights can also be used from 0-60 degrees (to the horizontal), and are available as Fixed Skylights, Manual Opening Skylights and even Solar Powered Opening Skylights. Sizes vary from 460mm all the way up to 1275mm, so clearly we have a flat roof skylight for every room in your house!