A strip-shaped support and insulating element for supporting and insulating a window frame with respect to a main wall includes: (1) a support part formed of load-bearing material and having (a) a first side surface engageable with the main wall and (b) a second side surface substantially perpendicular to the first side surface and supportingly engageable with the window frame, the support part including (a1) a first web that includes the first side surface and an inner side surface opposite the first side surface and (a2) a second web connected to and projecting at an angle from the first web; and (2) an insulating part along the inner side surface of the first web and pivotably connected to an outer edge area of one of the first and second webs such that the insulating part is pivotable between positions which expose or cover the inner side surface of the first web.