Plaster - again

[AntA]

Anyone know the difference between plaster whish is:

a) Manufactured to BS1191art 1:Type B1

and

b) Manufactured to BS1191 : Part 1 : Class B

Both are quoted from Hanson's website. The first is described as "Finishing plaster" and the second is described as "Patching plaster" in one place and "One coat plaster" in another.

According to BAL technical helpline BAL Whitestar is suitable for use on finishing plaster without priming, but what about the patches? BAL said ask Hansons, and Hansons aren't answering.

 

[brian c]

what are you trying to do m8..patch holes or plaster a wall?

 

[AntA]

I want to tile over it with ceramic wall tiles. The plasterer said he'd use one coat to save two visits (one to repair the base coat and then to apply top coat) and also because ultra smooth finish isn't needed to tile over. Mostly it's just a thin skim but in places it's 20mm thick.

I want to check that it's ok to tile over it.

 

[DHTiling]

I want to tile over it with ceramic wall tiles. The plasterer said he'd use one coat to save two visits (one to repair the base coat and then to apply top coat) and also because ultra smooth finish isn't needed to tile over. Mostly it's just a thin skim but in places it's 20mm thick.

I want to check that it's ok to tile over it.

You cannot use a tubbed disperson adhesive deeper than 3mm...and BAL technical didn't know that..?

Use a fast setting one coat as your plasterer suggested...then when dry you can revert back to the tubbed adhesive depending on tile size and type.

 

[AntA]

It's the plaster that is 20mm thick in places, not the tile adhesive.

Anyhow, it seems I can tile over it. I spoke to Hansons technical helpline and they said it's fine.

 

[dock]

You cannot use a tubbed disperson adhesive deeper than 3mm...and BAL technical didn't know that..?

You do surprise me..................surely Dave Wilson would have known (don't know any of the others in technical at this time so you may have spoken to one of them!!) - its common with all ready mixed adhesives because they contain roughly 25% water you can get excessive shrinkage if they are used extensively above 3mm thick. It is well known that some fixers "dub out" with it ..................but its not good practice

 

[jay]

as above you need to sort walls first any chance of pictures as it makes it easier to advise:8:

 

[AntA]

You cannot use a tubbed disperson adhesive deeper than 3mm...and BAL technical didn't know that..?

NO. This thread has gone off at a tangent. Nobody suggested using tub adhesive at more than 3mm. The 20mm is plaster depth.

 

[DHTiling]

What about the area's you said needed patching...didn't you say that you were going to patch that with tile adhesive...instead of patching plaster.?

 

[Aston]

i could have sworn when i read this thread yesterday that somewhere along the line you said bal had suggested filling in the patches with tubbed adhesive? i could be wrong so dont hold me to it...

anyway, if you have patches of upto 20mm thick, then use a one coat plaster. that can be used upto 20mm in one application. it also solves your problem about doing it in one visit....job done

ed

 

[lucius]

Just make sure you prime the one coat if using cement based addy
Lucius.