Remove the handle from the window and inspect it. Sometimes the metal bar sticking out from the back of the handle comes loose.
If the handle seems fine then it must be a problem with the lock inside the upvc window. To get the window open try inserting a small metal hook into the window lock and turn it to try and pull the gearing loose. Alternatively you might have to gemy the upvc window open with a wide metal bladed wedge/chissle.
Once you have opened the window you will need to find a replacement lock. Here is a link to a company that have a good selection of upvc window locks:
[quote="gothgirl123"]Tried opening our bathroom window this morning (on the first floor), the handle moves but we can't push the window open.
I suspect this means the mechanism inside has broken?
It is worth investigating to get it fixed? Is it something we could do ourselves?
Or shall we just replace the whole unit?
Thanks in advance for your advice![/quote]
I've had this too - caused by the PVC window sagging ever so slightly so it fouls the lower edge of the frame.
You can check it without damage - take a short piece of wood and try to introduce it between window and frame to lever it free. If that works then you have to get the window reset: the installer should do this if within the 10 year guarantee period. Otherwise it can be done internally without lifting out and resetting the slide hinges, but it needs planning and extra hands! (I've done it)
Replacing the whole window is unlikely to be necessary, but if the sliding lock mechanism is damaged or no longer useable, then that probabaly is the economic solution.
DIY how to tutorial projects and guides - Did you know we have a DIY Projects section? Well, if no, then we certainly do! Within this area of our site have literally hundreds of how-to guides and tutorials that cover a huge range of home improvement tasks. Each page also comes with pictures and a video to make completing those jobs even easier!