pva

can anyone tell me what background surfaces would DEFINITLY need a bonding agent?

Freshly plastered walls, especially if your tiling onto 'bonding' type plaster.

Also, wooden surfaces. :)

[Leatherface]

Plastered walls if using cement based adhesives - use recommended primer not PVA
Freshly laid screeds - helps reduce dust and aids adhesion of tiles.
Anhydrite Screeds - always prime -remove laitance first ( top flaky layer )
Wood - usually.

Mapei sell a number of tub adhesives which do not require primer onto plaster.
Also many of their flexi adhesives do not require primer onto wood or some concrete surfaces.

[jaimie s]

Just to add my my 10p worth. Depending on what company adhesive your using. Most have spec sheets you can read and decide from there. If in doubt ring company up. Different adhesives have different additives added to them so difficult question to answer.

thanks to all.much appreciated.

[Varley]

The only time you could get away with using pva would be on a concrete floor. PVA is only a sealer, not a bonding agent!

[sparky]

what is the best bonding agents i use the bal but was wandering if anyone got better stuff or better prices i ve paid £12.99 to cover about 6m2 . Although saying that i am not trading yet and have to pay the same as the public

[Leatherface]

Originally Posted by sparky

what is the best bonding agents i use the bal but was wandering if anyone got better stuff or better prices i ve paid £12.99 to cover about 6m2 . Although saying that i am not trading yet and have to pay the same as the public

Always use the adhesive manufacturers recommended bonding agents.

does anybody prime plasterboard when using powders ??

[Leatherface]

Yes - I use a 3 / 1 soultion of bonding agent

3 water 1 agent with these walls

[tjsmiler]

Ardion P51 (Ardex) is good stuff sparky, but you should only really use a bonding agent that suits the muck your gonna use.