You do not need permission to demolish a chimney breast however, if you demolish the breast on the ground floor you have to make sure you have enough support in place to support the breast on the floors above it? A builder would be the best person to carry out this work.

best regards

CKG

You wont need permission unless its a listed building but you will need to follow building regs when you support what remains of the chimney.If you share your chimney with a neighbour you will also need a party wall agreement.Your best bet would be to get yourself some advice from a structural engineer before going any further.

As its classed as structural works, you need to inform building control.
You will also need a structural engineer to calculate steels etc which may be required.
BCO will inspect the work and issue a completion certificate.
A good general builder will be able to carry out the works.

Hi you may need consent if it a listed building, allso if the chimney brest continues above the ground floor you would need building regs for any supporting work once the chimney brest is demolished.A good general builder would be able to the work.