Advice sought. Planning regs.

[classic33]

Any structural work automatically requires approval under Part A1 and A3 of the 'Approved Documents' under Building Regulations Acts... contact your LA Building Inspector who will; come out to inspect any structural work that's been done without approval.

Any work done to a party wall between a pair of semi-detached or terraced houses also requires the people doing the work to arrange a Party Wall Agreement before work sartsto make sure that any work done to the jointly owned party wall doesn't adversely affect the neighbouring property

None of that done. Walls removed on the cheap.

 

[Archie_tect]

None of that done. Walls removed on the cheap.

Then speak to your LA Building Inspector [urgently if you are worried about the possibility of collapse] to arrange a visit- they will have to provide your LA Building Inspector with evidence of what they've done and if he's not happy it may have to be opened up for him to see the work and he may require them to pay for a structural engineer to assess the beam spans, loading, loadbearing supports and signs of movement, especially any damage on your side.

 

[Darren Gregory]

As @Archie_tect has already said, you need to contact your Local Authority Building Control, not Planning as what you describe is internal and therefore not development. Probably worth a call to your home insurance provider as well, they might offer some advice on where you stand with any damage to your property.