sm_jamieson wrote:

On 25 Jan, 15:24, Tony Bryer wrote:
On Thu, 25 Jan 2007 13:52:16 +0000 Dave Fawthrop wrote :

Yes! Normal double glazed windows have the *facility* to be locked
totally closed or slightly open. IMO much better than trickle vents.I'm not so sure. ISTM that on ground floor windows locked slightly open
is akin to a notice saying "insert crowbar here".

I agree, not the best for security.
But the point is just to get the BCO satisified with the required area
of trickle ventilation per window without a huge air brick in the wall.

OTOH once the BCO has effed off, an airbrick is easy enough to get rid
of..vents in windows are not.