Abstract: A sealing or guiding assembly for sealing or guiding a corner of a closure member such as a window (109) for an opening is disclosed. The sealing or guiding assembly is attached to a frame (8) comprising panels (22,24). Strips (91) of flexible material extend towards and meet at the apex of the corner and are shaped to receive the closure member (109) at the corner and are adapted to be supported by a corner support which forms part of the frame (8). A flap (170) of flexible material is joined to the strips (91) in the region of the corner and bridges across the corner between the strips (91). The strips include inner lip (102) and outer lip (103). The joins (160) and (162) between the moulded flap (170) and the (preferably extruded) material of the strips (91) is obscured from view by the lips (102) and (103).