The Natural Philosopher wrote:
Grunff wrote:
PVA them first.


Don;t bother. Waster of time. Makes the adhesive take longer to set as
well.

Well, although I can't say I've tried with and without, my reason for
always PVAing is to provide a dust-free surface. Both ply and PB tend to
be quite dusty, especially if you've been plastering/filling in the
room. A coat of PVA provides a sound, dust-free surface to tile onto.


--
Grunff