Building regs don't apply to non-structural alterations.
But if your flat is part of a block 3 storeys or more the you should conform
to building and any fire regulations

If you want to conform then
Your fan would be better if extracting at 60 l/s. If a cooker hood then 30
l/s will suffice. You also need some fresh air ingress to the kitchen.

Your 2 x 12.5mm board and 3mm skim will be OK.

Don't forget your 1/2 hour self closing fire door and intumescent strips,
and make sure your means of escape from other rooms is not affected.

Also make sure any management company is aware of the alterations and
approval is given.

dg


"Dave D" wrote in message
om...
Hullo
I am shifting my kitchen to be internal in a 2nd floor flat.
1) I am putting in an extractor fan at ceiling level does it have to
be a 30 or 60 LPS ?
2) I have an internal window to a bedroom, I will be closing this:
Does 12.5mm plasterboard have the required fire retardency. Can I use
glass bricks/special glass and if so will it meet regs ?
Cheers
DD