Should I be notified if the two flats below mine are converted to one?

The neighbours in the flat below are probably at an early stage of the intentions/idea of converting the two flats and would not be entitled to make a formal application to the Local Authority for planning or building control at this stage as they probably need to do a feasibility study first. Upon receiving the structural surveyors report it would then be expected to proceed down the formal route to obtain planning/building control consent. For them to ask you for access, you would have every right to enquire why.

A "Party Wall Act 1996" letter should have been drawn up for you to sign and a reply to the clients. You can find details and examples of these on the Web by searching Party Wall Act.

First. You should of been notified If they are knocking out load bearing walls and replacing with steel RSJs they will need building regulations You should of been notified about this and you should contact your local council planning department to make sure they have done this Some builders have a habit of by passing planing regs and building regs as they have to await approval and it costs money for this and have the calculations done by a structural engineer so the RSJs can take the load

If works haven’t been started then it is acceptable to get your surveyor out to see if your intended plan will work following your surveyors report planning would then need agreeing too to make sure all works complies with building regs, a letter/contact should have been made prior to make you aware of the surveyors visit and if access to your flat was possible on the requested date and you should have signed and agreed this instead of surveyor turning up on the day and expecting to gain entry.