Chimney breast removal help

[NutsForMutts]

Hi, have just found out we need building control to sign off on our chimney breast removal, running between our now knocked through kitchen diner. (so middle of the house essentially) Strangely the builder is getting other approvals but has left this one to us, retroactively. They've removed the full chimney (stack was taken off when we converted loft) but they also somehow didn't anticipate that it would go over to the party wall. So we have no party wall agreement. The adjacent property did same exact removal while we were living here, with no PWA, but different owners now. Builder is saying no need for a flitch beam, but I'm concerned about what building control will say once we apply for regularisation. Next door has a flitch beam. Our house currently has subsidence that we are separately trying to remedy. Any thoughts or advice? TY!!

Sounds confusing? If the stack has been removed completely then what would the flitch beam be strengthening/ supporting ? Unless the floor/ ceiling joists went into the breast, so would need additional support ?

hi @Diyextension. I know very little about buildings and how they are supported. It just seems strange to me to have this large space now (kitchen and dining room) without a load bearing wall or a beam to support the first floor rooms and second floor loft. The loft runs above part of the affected first floor and the part without the loft has a concrete tiled roof. (House is a Victorian terrace)
Because we have quite dramatic open cracks from subsidence, thought to be caused by a tree located just at the party wall join in the back of the house, I am very nervous about any scope for rooms to collapse. Right now there is just a hole where the chimney was and the builders are planning to build out the joists. The eventual plan once the subsidence calms down (tree is being removed and structural engineer says ground will rehydrate and lift the house back up) is to add a steel box and have glass doors spanning the back of the house.
does that all make sense? Sorry it is confusing!!

What did your structural engineer say was needed, before you took down the load bearing wall?

Hi @dreamersdown He didn't actually say. Just that steel wasn't needed in the vacated chimney space, but that the upper part of chimney left behind would need supporting. BUt we ended up taking out the entire chimney, it is all gone. Builder is saying no flitch beam needed and just putting in joists.

The SE's main role was to help us diagnose the subsidence and how to deal with it. Main message was to remove the tree causing it and wait six months before installing glass in the back.