On 9 Jan, 17:08, Jacko wrote:
I'm a scout leader and we've just had a maintenance visit from the gas
company. We have an Open Flue Boiler (?) + another gas appliance in
our kitchen - we've been told that the ventilation is inadequate and
needs improving. Apparently it needs to be 575cm sq (ish) due to
legislation changes during last year. *They will provide advice but
it'll cost and its not cheap, he did say that we could use air bricks
but they wouldn't be any good because they don't let suffient air
through so we'd need dozens of them for it to be adequate.

Any help regarding type of grills, size of hole etc. would be really
appreciated as we are currently unable to run the boiler until its
sorted.

Thanks in advance

Jacko

Look up a ventilator supply specialist (IIRC Fans and Grilles used to
have a place in Leeds).
Contact them and ask for a price for a weatherproof vent with the spec
you have been given. Larger is ok.
It is not permitted to have a fine mesh in the vent as they clog with
dust but if the suppler is advised it is for a combustion vent they
will supply a suitable unit, possibly with a large (bird and vermin
proof) mesh incorporated. Go for metal not plastic as vandals have
less effect.