One might also like to consider glazed side frames, glazed vertical ‘windows’ that sit beneath the pitched roof lantern. The principal reason for including side-frames is to create a more impressive design statement, both internally and externally as they approximately double the height of the overall lantern structure. Because of this though, one generally finds they’re not suitable for the majority of extension projects but they’re particularly suiting for apertures above a stairwell or landing.
A popular misconception is that side-frames contribute more light to the space below, however it’s the size of the aperture which determines this; with or without side-frames. So in essence, side frames are primarily a decorative feature rather than a practical one. Opening vents however can be incorporated into the side frames leaving the roof above untouched.