Thanks for help from the group. Had a lousy plasterer some time ago. Decided
I couldn't do worse so I tried.
Have skimmed a wall and there are some hollows. If I want to skim it again
do I need to roughen the surface for the second coat TIA

"Sploop" wrote in message ...
Thanks for help from the group. Had a lousy plasterer some time ago. Decided
I couldn't do worse so I tried.
Have skimmed a wall and there are some hollows. If I want to skim it again
do I need to roughen the surface for the second coat TIA

Generally when I have to re-skim a wall a couple of coats of PVA
adhesive (suitably watered down) is all that's needed to retard, and
subsequently help the new skim coat to adhere. The more porous the
substrate being plastered onto the neater the PVA/water mix, I think
the back of the tubs suggest about 1:5 (PVA:water), I like mine to be
a little stronger, typically 1:4 or 1:3. If you're a novice plasterer
and the walls are un-decorated (and thus highly porus!) I'd suggest
giving the walls 3 or even 4 coats of PVA/water to really retard the
plaster that you put on...why make life hard for yourself!

Good luck,

Mark