"Tony Bryer" wrote in message
...
In article , Peter
Taylor wrote:
No modern window is designed to take any structural load. PVC window
manufacturers have worked out how to do it using aluminium structural
posts
with jacking plates, which fit into the junctions between the frames and
concealed by PVC sheet, but the actual fitters are paid per window and
hardly ever bother to do this properly. There are very many claims and
court cases over this.

Check out http://www.expertexpert.com/bays.htm for more on this.

Excellent Tony, when I read it I realised I could have written that page
myself )