Changing window hinge position

[sophiecentaur]

We recently moved into a house with UPVC windows. Most of the windows are hinged at the top. It would be much more convenient if some of those could be changed to have hinges along the sides.
I am wondering how much of a pain that job could be. Are there a whole range of hinge standards from the different sources of windows or is it likely that I can easily buy the appropriate hinges on line? The windows were installed in the late 90's.
I would appreciate some advice about this.
Cheers

 

[Gazman16]

95% sure without even looking that its not doable.
You would likely need new locking mechs fitted and would be left with holes where the old handles were.
If the top hung sash's are over 700mm wide side hung hinges probably couldn't take the weight.
If there are any problems you most likely wont be able to get spare bits of window frame/sash etc.

So 95% chance not possible and 80% chance if it is possible it will cost more to get someone to do it than to replace the windows.
Feel free to post a pic just encase they are small easy ones but new windows are most likely the way to go.