Well, not very well it seems, I have tried dampening the walls, keying in
and two differing makes / batches but the result
is still the same - I leave for a few days and the bonding is very weak - a
fingertip touch and it comes unstuck.
Have tried priming with 1:5 PVA but even worse, so wondering if its just too
warm to do this at the moment ?
(which I can't believe)

Anyone any ideas ?

Thanks,

Nick