Converting 1-bed flat into a 2-bed

[james@longley-investments]

I own a purpose built (by my grandfather in 1965) two storey residential building which contains ten identical, 1-bedroom flats. Each flat has an entrance hall with doors leading to a bathroom, a bedroom, a very large living/dining room (20'x12' or 6.15mx3.66m) and a kitchen. There are also sliding doors from the living room into the kitchen. They're rarely vacant & there's often a waiting list for tenants. However, one's just become free and I am planning want to convert this ground floor flat into a 2-bed with a view to converting at least 5 out of the 10 in the coming years.
The current kitchen will become the 2nd bedroom, with a new stud wall dividing it off from the living room. The new kitchen area will be at one end of the 20 foot long living by a door leading out into the communal garden (ie. fire exit).
Was going to put a Building Notice in 2 days before work but wanted to ask members if I was missing something from the equation? Thanks in advance. PS. THe building has a new regulation fire alarm & I realise the heat detector from the old kitchen needs to move. :)

[pilman]

Obviously no planning permission is required, so if you are aware of the current specifications in the various parts of the Building Regulations, that is what will be needed to create a successful re-development of the flat.

Don't forget that the horizontal division with upstairs and the vertical division on the same floor may need to be improved for sound control if the flats were built in 1965 when standards were much different than they are today.

You may need to place sound insulation into the void above the ceiling to comply with current regulations if you require a completion certificate from Building Control.

[Tipper]

The location of the kitchen with respect to the fire exit from the rest of the flat may also be an issue particularly on upper floors due to the need for a protected escape route.

May be better just to leave them as is to avoid the BCO insisting on changes to comply with the latest regs, including sound proofing as said above which can cost a lot of cash.