Finishing off Double Glazed Window.?

Question

My Builder has just finished putting in a new double glazed window. Because it is smaller the surround is showing the old timber. He has pointed out that you cannot plaster over this as it will not take properly. I want a nice flat finish, not architrave.
Any suggestions or products I can use for a finish other than plaster. Thank you.

Answer 1

I can't quite picture what you need to cover. Do you mean that the new window is thinner than the old window, thus revealing the wood framing because the old surround doesn't reach the window anymore? If this is your problem, you can fill the gap with joint compound, let it dry, and then tape over it with drywall tape and more joint compound, feathering it out so you don't see the tape. For filling the gap, I recommend using a quick setting joint compound that you have to mix from powder, because it has much less shrinkage than the premixed joint compound. For taping, however, I find it easier to use the premixed joint compound because you've got so much more working time before it sets. Sand it lightly, prime with PVA primer, then paint.

You could also use wood moulding nailed to the surround to cover the gap, but the thickness of the moulding could be a problem.

If your new window is smaller in the height and width, you could make a new surround out of wood ripped to the proper width, nail it in place, and then cover the gap between the wall and the new surround with casing, much like what is done for a door jamb.