A building window for mounting to a rough opening defined in a stud frame
wall. The building window includes at least one sheet of transparent or
translucent material set in at least one sash which, in turn, is disposed
in a frame. The frame includes a first mounting flange that extends
outward from an outer surface of the frame in a direction approximately
parallel to the plane of the at least one sheet of transparent or
translucent material. The frame also includes a second mounting flange
that extends outward from a first side of the frame in a direction
approximately perpendicular to the plane of the at least one sheet of
transparent or translucent material. The second mounting flange is
configured and arranged to be secured to a perimeter edge of the rough
opening defined in the stud frame wall.