Replacing Sash windows

21 Jan 2010
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United Kingdom
Hi, i am looking to replace sash windows.
At present these have been replaced with single glazed upvc window, but the sash wooden frames have been left in and UPVC 50 mm strips glued all round.I want to remove the whole thing and replace with dble glazed UPVC windows.
I have been told that this involves msking good brickwork on the inside using wood. How is this done?And whats best way best way to do this?
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I've never fitted plastic windows but if you take out the old sash box frame out and then fit a double glazed sash box frame in it is deeper and will stick out into the room. You then have to pack out the architraves. Is this what you meant?
Thanks for your reply.
I was told that when the fullsash frame is removed, the inner leaf of brickwork has to be made good to line up with the outer lef. Hence the timber fixed into brickwork. Then all plasterboarded and skimmed.
Has anyone had sash windows replaced with standard UPVC double glazed units? And is this the correct way to finish off?
Remove ALL timber so you are left with a brick opening, fit and fix the window to the outer skin so the inside face of the window is flush with the inside face of the outer skin of brickwork, from this position you can physically finish the outside, including the arched head if it has one, this will then be weather proof allowing you to carry on with the inside in your own time.

Once the window is in it'll become apparent what is needed, what i do is use rough sawn 4x2 to box out the sides and head, then cut a new windowboard with correct overhang and including horns, either no nail or silicone it down or fix with screws if its a painted one. Then plasterboard over all the 4x2,reveals and front face but here you MAY have to use some bonding and then skim depending how much plaster fell off the wall when you removed the old timber work.

All in all its one of the most horrible, dirtiest and dustiest window jobs you can do, good luck :cry:
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The above is one way of doing this but I find using plaster board against brickwork and then skimming can cause cracking where the two meet.I do it the same way but in stead of plaster board and skim I use timber liners and a nice ogee architrave which is more in keeping with the style of property.But as he says it is the dirtiest job we fitters face 1 tip lay loads of dust sheets and an extra 1 directly underneath so once you've got it all out and brushed down you can pick this 1 up and get rid of most of the crap leaving a clean sheet under.
Forget the timber and plasterboard use bricks and bonding, bricks upright work well.

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