changing hnges on upvc d/g windows...

I done this just the other week. The hinges should be the same size and therefore just screw into the holes the originals have come out of. There was certainly no scope for me to mount them in a different position.

Beware though how heavy the unit will be. I replaced a side opening window roughly 36" x 18". It was bloody heavy.

Steven.

The new hinge should be almost the same size, but could be 10 - 15mm longer/shorter, it may even be wider/narrower. I had to trim my frame with a chisel to accomodate the extra 1mm width. Make sure the new hinge is positioned at the hinge end the same as existing one. I'll also reiterate the previous poster's comment about the weight, tie a rope around it and get assistance, they are always a lot heavier than you think... and you really don't want to drop it.

Peter

Frame first, then sash.

As others have warned, you will need help to offer up the sash for fixing. If it's a big one you might consider de-glazing before you fit.

Thanks all, that's helpful - is it necessary to pre-mark the screw locations for the sash, or does it simply slot into an obvious place? I'm especially worried about the upper hinge, as it's quite near to the eaves and I'll stuggle to see it clearly to mark-up.