Val, this could be either of two things. If the windows have been in over 6 years then it could be the window hinges
(proper name: friction stays) that have worn causing the window to drop. If the hinges look O.K then it is the sash that has been incorrectly packed up. When a glass unit is put into an opening sash the air gap between the glass and the sash should be packed up with glass packers to keep the sash square. To re-pack the glass you will need to remove the pvcu beading around the glass unit and put in glass packers on both sides of the bottom corner on the hinge side not the opening side. Then do the same at the top coner of the sash on the opening side this time. Keep adding packers to both corners until your sash is to the right height. We can supply you with replacement friction stays or a selection of glass packers. The company I work for is "safe n sound ltd" and we supply replacement hardware for pvcu windows and doors to enable them to keep working. We sell products nationwide and have a website where you can identify and buy a wide range of product. The website is "www.safensoundltd.com". You can also contact us on 01422 378558, 9-5 mon-fri.
Chris White
April 2005