Rex

Hi thanks for your response! The riser has water pipes and drainage stacks that benefit each flat in the HRB. I'm doing a BSR application and so need to detail compliance with Part B of the Building Regulations for a bathroom refurbishment - there is an existing access panel to this riser which is not fire rated because the block of flats was built in the 1960s (and the previous asbestos panel has been replaced with an mdf panel). The 'riser' is fire-stopped at each level though, and so only the pipes pass through the concrete floor. So I am not sure whether the access panel needs to be fire compartmented in the first place as it might not count as a 'riser' given it has a concrete floor and ceiling (with only pipes passing through). Both APD B and the Fire Safety in Purpose Built Flats guide don't seem to help with this specific scenario.

If a shaft does have floor separation, does there need to be fire compartmentation of the shaft walls on each level? I can't find a paragraph number in Approved Document B that explains the answer.

Where there is a communal services riser in a block of flats, but the riser is fire-stopped at each floor (i.e. there is a concrete floor and ceiling on each level) - is it necessary to have a compartment wall that faces into the flat? I've looked through Approved Document B but I can't find a satisfactory answer. In this scenario, would the whole floor be a compartment rather than the riser itself - or would the riser still have to be a compartment?