"Christian McArdle" wrote in message
...
That will work, but I doubt they would allow you to do it. Or will they?

Well Kingspan say it is OK even without any air gap at all. I don't know
if
it was the builder or the BCO who insisted on the vents.

BCO, I'm sure. They like an uninterrupted air path. The cross batons that
the tiles are hung off blocks the flow. The makers of the membranes say it
is not necessary as the water vapour will just float out of the membrane and
through the gaps in the tiles.