I am a handyman. My clients (6 leaseholders, 3 storey house, lower than 11m) asked me to change their custom made gas meter cupboard located at the rear of the building as the chipboard previously used started to decay (see and ).

I had a look at building regulations on gov.uk but also found a document by Cadent which gives slightly different rules, e.g. Cadent says the meter cupboards shall get locked whereas gov.uk says they must not get locked unless ever resident gets a special key for it. Either way, my clients asked for it to be without lock.

In order to comply with BS 476-7:1997, Class 2, I need to treat all timber with a fire resistant paint. Ideally I would like to use clear top coat varnish (2 coats required by law). Can you confirm that 2 coats of top coat are sufficient or does it require a fire resistant uncercoat also? Prices seem to vary a lot (from £40 to £200 per litre) so any advice on an affordable brand/product would be much appreciated. I assume that any such fire resistant paint will have to come with a certificate that I need to pass on the "responsible persons" which, I assume are all 6 leaseholders/share of freeholderd. Is this product sufficient?

I was initially planning to use exterior sealant to seal the gap between cupboard and wall. Will I have to purchase fire resistant sealant as well or is the usual sealant accepted? 

Any other legal issues connected to replacing the old cupboard (e.g. can attach it to the wall with angled brackets or does it have to be free standing?) that jump into your mind would be much appreciated.

You aren't going to comply with Building Regulations applying a paint system to wood.

Most marine ply when sold for Reaction to Fire EN 13501-1:2018 is Class B (generally B-s2,d0).

The national standards BS 476 have largely been dropped due to being what they call small scale tests and following government announcement when parlaiment recently returned these will be fully removed from Approved Document B come 2029.

To comply with regulations you need a tested system - I doubt your clients can afford the £1,000's required.

I would avoid any paint system that claims it creates fire resistance by application - when you read the actual report in detail there are many caveats including what the product has been applied to which is often the material impacting the test result.

You won't get a certificate of any value worth passing to your clients.

Use a suitable non-setting intumescent sealant between timber and wall and where the pipes pass through.

As to the key it would be foolish not to apply a key - most gas meter boxes have a triangular key which residents and meter readers hold whereas kids messing about typically don't - given the size of the pictured door I would suggest top and bottom as opposed to a single lock in the middle.

Of course you could use a powder coated or glavanized steel door which would be non-combustible and would not suffer from long term rot.