Morning

Whats the best Bal primer to seal a plaster skimmed wall in my bathroom,SBR or APD.Going to be using Bal Rapid set flexi ad.
Do you need to seal ext grade plywood before you tile with Bal Rapid set flexi,its a panel to hide the shower valve.

SBR is a water based polymer and APD is an acrylic primer. I generally use the SBR - ( I like the smell - like new carpet!!) But both should be fine as they're basically doing the same thing and stopping moisture soaking into the walls too quickly. I think the official answer is to use the APD tho, although some on here may say otherwise.

Thanks mate.
I did look on the Bal website and they say when using rapid set flexi use APD for sealing plaster.Do i need to prime a plywood wall panel when using rapid set flexi ads or tile straight onto it?

Cheers

Sean

Hi CDS
I use SBR on everything even to seal walls that have been covered in emulsion but do not use it on gloss!! If you have to tile on tile (if this is what the customer wants) mix the SBR 3 parts water to one part SBR and add some powder adhesive (that you will be using to fix the tiles)
to a thin past brush on and allow to dry this gives the best grip ever but make sure that the tiles are fully cleaned with a strong detergent and fully dry.
SBR is the one to use..
Trev.

I'm not sure why (maybe someone could comment) but I don't believe bal recommend Rapid set flex on ply wood walls.... You'd be ok with tubbed bal white star or Grip for this. Only need to prime the edges and joins but as previous post suggests many will prime all over just to be sure. If you want to use cement based then probably fast flex but this isn't cheap unless you can get discounts from your local supplier.

Ply on walls the bain of my life

I'd be tanking the ply, brown grout joints are not pleasant