Rectangle window in arched opening question

[DevlinT]

Hello all

I live a typical Victorian house. I am looking to replace some windows.

As per the picture the window opening is slightly arched at the top as seen from the outside. Looking from the inside there is no arch. The window (current and new) are rectangular in shape.

My question is - how do they finish the top arched part? Is it a uPVC trim? If so, is there not a void behind that needs to filled?

Thanks

 

[mrrusty]

Like so many houses, that would have originally most likely been a box sash, with the frame and boxes behind the outer brickwork leaf. The long horns on the internal cill are another indication. There won't be much of a void behind - it's a solid wall - no cavity.

 

[DevlinT]

Great, thanks @mrrusty

Is the attached diagram a fair depiction then of how this has been constructed?

 

[mrrusty]

yes, except the window would stand on the external cill, if it hasn't been butchered you'll probably find it shaped to divert water outwards.