Hello again. Doing my bathroom floor in the next day or so but already have a little bit of confusion, I will be putting ply down on top of the exsisting floor boards (exterior grade), now, i thought you were supposed to prime the ply, i've just bought Bal-prime apd but it does not mention ply on the back of the bottle it only mentions normal Gypsum Plaster , Cement Floors, and Anhydrite Screeds, so i contacted Bal's tech support and they say you can use it on Marine/Exterior grade ply but it is not needed, anyone care to advise, Cheers.

They might say it's not required as the adhesives they supply can/do have priming agents in them already. What adhesive did you say you were using?

Hi Dan, forgot about some adhesive already having it mixed in, but any way, it's Palace Multiflex 1 part rapid set.

Not too sure about the Palace range myself mate. But maybe BAL thought you were using their adhesive and assumed it isn't required for your specific application? I'd give Palace a call perhaps.

Ok will do, thanks again.

Ok, Palace recommend a palace primer diluted 1 to 3 parts with water, could i dilute the Bal prime to the same ratio.

I don't see why not personally but sometimes the manufacturers can get a bit arsey about what's been used with their adhesives. Plus in a way, I suppose there could be compatibility problems.

if its marine, exterior ply then your ok using multifex by palace. i use it lots. 15mm minium for ply. mix adhesive strong and using a 10mm half moon shaped notched trowel should be fine. nice bed of adhesive to fix tiles to. just my advice.

Justy to add, i just bought exterior ply but one side is dark brown the other side light brown, which way up does it go, or is there no difference.

no difference mate just put ply either way

Thank you