Bonding coat

[IAmMrB]

hi all,

I removed some tiles as they were a bit worse for wear as was the plaster so I chopped it back to the brick. The plan was replaster the area I took back to the brick and then re tile. I was told by the tiler he could tile straight over browning but I used bonding as I read it took to brick better.

I put bonding coat on and trowelled it up smooth with the mind set of tiling to it. I have now read that this is a bad idea as the moisture will be sucked from the tile adhesive.

So. Can I put Finnish plaster over the s,oohed bonding coat or will I have to rough it up ?

Thanks

 

[roy c]

You cant tile on bonding or browning!! Best to knock it off and use sand and cement render, no need to skim it just tile onto the render coat, I would give it a scratch for a better key for the tiles...

 

[IAmMrB]

Hi Roy,

Surely it's ok to tile onto finished plaster ? The tiles in my kitchen are tiled over multi finish over browning and have been fine for the past 10years.


Removing the new bonding and applying sand and cement isn't really what I'd like to be doing as I have bonding and multi finish.

What I want to know is whether the bonded coat needs to be primed / scuffed before the finish is allied ?

 

[roy c]

It's up to you but I would not tile on bonding or browning...

 

[IAmMrB]

Okay Roy - thanks

 

[roy c]

Sorry IAmMrB I know I was banging on about not tiling on browning and bonding but It was in my mind that you were tiling a bathroom or shower!! So if the area is water free then it is probably ok over bonding and browning if it has been skimmed. Sorry for the mix up.

 

[Doggit]

The problem with tiling straight onto bonding, is that if the grout goes, and water gets in, then the bonding will just crumble, but in a kitchen, you should be fine. You'll need to apply a PVA mix to the surface of the bonding before you either plaster it, or put the tiles on. As without the PVA, the bonding will just suck the moisture out of the tile adhesive, or the plaster.

 

[IAmMrB]

Thanks for the advice chaps