Covering window arch when installing straight window

[Tedds23]

Hello,

The original windows in the old section of our Victorian house have arched lintels, but the new windows in the recently-built extension have straight windows.... In the old section, a previous owner fitted straight windows and (somehow) covered and rendered the arched portions. The problem is that whatever they used to cover the arches has started warping and a gap between the window and the wall has started appearing. I was thinking of replacing the windows at some point, which would also allow me to fix the arch issue. What would be the best way of filling the empty arch portion at the top of a straight window? I would like to maintain a straight profile (no uPVC arched trim), and i think that replacing the arch lintel with a straight one would be too expensive. thanks

 

[Bullet-Proof_Biscuit]

It would have originally had sash windows which are larger than the opening in the outer leaf, they sit in a recess created by the inner leaf opening being bigger than the outer leaf, this is called a check reveal. If you refit new sash windows with this method you will only see the front top frame of the window where the arch lintel is, no infill required. Google search for 'check reveal' to see what I mean..
Note when measuring sash windows to suit a check reveal (aka the correct way to fit sash windows, which isn't done more than half the time), you need to measure the outer leaf opening, and a add extra measurement on so the sashes sit in the check reveal correctly, it is typically about 40mm per X & y axis, subject to the dims of your check reveal and the frame thickness of the sashes you want to use. If you don't think you have check reveals, what usually happens is the UPVC fitters leave the original sash boxes in and fit the new winows in this smaller opening, so you might just have to chop the old wooden sash boxes out to reveal the reveal (ha!) and away you go.
Hope this helps, I'm going through the same and this is what I've gleaned from here and other internets..
HH

 

[Tedds23]

Thanks, very useful information

 

[Tedds23]

It would have originally had sash windows which are larger than the opening in the outer leaf, they sit in a recess created by the inner leaf opening being bigger than the outer leaf, this is called a check reveal. If you refit new sash windows with this method you will only see the front top frame of the window where the arch lintel is, no infill required. Google search for 'check reveal' to see what I mean..
Note when measuring sash windows to suit a check reveal (aka the correct way to fit sash windows, which isn't done more than half the time), you need to measure the outer leaf opening, and a add extra measurement on so the sashes sit in the check reveal correctly, it is typically about 40mm per X & y axis, subject to the dims of your check reveal and the frame thickness of the sashes you want to use. If you don't think you have check reveals, what usually happens is the UPVC fitters leave the original sash boxes in and fit the new winows in this smaller opening, so you might just have to chop the old wooden sash boxes out to reveal the reveal (ha!) and away you go.
Hope this helps, I'm going through the same and this is what I've gleaned from here and other internets..
HH

And what about if I wanted to replace sash with casement windows? Being that casements open outward, would that be a problem? Thanks

 

[Bullet-Proof_Biscuit]

No issues with that, that would be called a 'brick to brick' window installation. Just won't look as good as sash