Cracks in Bay Window

[Katy Hawkins]

Hi
I’m a new poster so apologies if I do anything wrong here.
I just noticed this morning some cracks on the internal walls of the upstairs Bay. There are no cracks in the downstairs at all.
I believe the Bay has dropped some time before we purchased the house a year ago. We had the glass replaced in the windows when we moved in and the fitter commented that the Bay had dropped quite a lot at some point. There were no cracks visible then so we just decided it was historic.
There are some large gaps on the external wall which I hope you can see in the pics. These were there when we bought
I’ve gone into panic mode so just want some advice about next steps? Should we contact an SE or a builder? What could be the possible cause?
Thanks and of course, ask me anything that I’ve missed that might help

 

[^woody^]

Commonly related to the work done to renew the frames, and/or the hanging tiles. Either some movement from installation of the frame or loading from the tiles.

These tend to be semi-progressive in that there may be some ongoing movement and opening up of the crack, up to a point when it then stops. But there then remains some seasonal movement - so anything like pollyfilla just re-cracks.

Normally some metal straps are fitted to restrain the bay timber frame, and then the bay re-plasterboarded.

Builders may be experienced in the problem or repair, but often are not and just guess. Generally, you should never never rely on the opinions of builders that would benefit from the work they may recommend. Therefore, independent advice and remedial work specification should come from a suitably qualified professional - SE definitely or building surveyor maybe.