Preparing an existing brick wall for dot and dab.

[tristos]

Firstly im a newbie so hello, been reading for a while and just got round to joining.

I have two existing brick build cavity walls where i have removed lime render or similar, not too sure presume its lime as on of the walls in the room is cob.

I have brought Cementone rendabond PVA to get the wall sorted prior to D&D

I would like to know what ration i should mix the PVA with water

Cheers

T

 

[PrenticeBoyofDerry]

It should tell you on the product, it is always best to follow manufacturers instructions, as some differ.
But normally 4 or 5-1 for first coat, then a bit stronger for second coat, 3-1.
You can actually get away without priming the walls for DnDing, but it wont hurt to do so!

 

[tristos]

Thanks for the response, its hard to tell how old the walls are but i think they probably are 50 years plus maybe more.

you think two coats then?

 

[PrenticeBoyofDerry]

Two coats, one the day before and the second should be allowed to go tacky before you apply the dry wall adhesive.

 

[trowelmonkey1]

board adhesive doesn't mind lots of suction so i normally don't bother to PVA unless i need to consolidate a powdery surface, usually where i've taken old lime off too.

 

[jrplastering]

im with trowelmonkey on this one, d&d doesnt really need pva applied, but i aslo do if i have removed an exsisting powdery coat I.E lime plaster, just to keep the dust from getting between the wall and the adhesive, i would say one coat of glue, let it go tacky, then get sticking mad.
happy dabbing.
JRP