Hi, in this tutorial I show a common way off raising the window sash (hopper, opener) upwards to help clear the window frame when installing a new style replacement window lock that where the locking cams may be to long as the most standard size is 8-9mm these days. This will vary from window to window but this is just me showing what we find works well. Any questions please drop a message or email us at assist@dgpsuk.com
Link below to where you can purchase new window locks if this is something you are looking for also..
www.double-glazing-parts-spar...
Thanks for watching and hopefully this helps someone or a few of you :-)