Common bodge from the past when the windows were one integrated unit. Install from the inside, seal on the inside, non-sealed outside so water gets in between the window and the brickwork.
As I understand it, window tech has moved on a bit and the panes are installed after the trim has been fitted allowing the installer to do the correct sealing on both inside and outside without the need for a ladder or scaffold.
They can still not put all the correct seals on the outside, decorator said ours, done about three years ago, had been bodged by not going up on a ladder to do the outside.
For some reason I was user124137 for a bit back there.
Common bodge from the past when the windows were one integrated unit. Install from the inside, seal on the inside, non-sealed outside so water gets in between the window and the brickwork.
As I understand it, window tech has moved on a bit and the panes are installed after the trim has been fitted allowing the installer to do the correct sealing on both inside and outside without the need for a ladder or scaffold.