Tiling Screed'd Floor - PVA first, Y/N?

Arfa__

I'm planning to tile our conservatory floor with bog standard ceramic floor tiles. It currently had a thick layer of screed down, which is nice and level. I was planning to lay straight on top of this, but reading some guides online, suggest spreading a dilute PVA mix down first. I never did this when I tiled the kitchen floor about 8 years ago. That was straight onto self levelling stuff and that's been fine...

What does the PVA achieve? Is it essential? Should I do this in my case?

Mayflower10cat

I have no idea at all what it does either!! But when our very nice tiler did our new conservatory floor, he PVA'd it first.

dave82_2

I would imagin it just stops the concrete floor soaking up the tile adhesive?

Mayflower10cat

dave82 wrote: »

I would imagin it just stops the concrete floor soaking up the tile adhesive?

Yes, that sounds very likely.:)

phill99

It aslo stops teh concrete producing dust which reduces the capacity of the adhesive to actually adhere.

andyhop

Do not use PVA for any tiling preperation

You need to use a Bal or Mapei tile primer

Something like Primer G from Mapei, This is a synthetic primer and unlike PVA does not reactivate when wet

Michtaylor09

andyhop wrote: »

Do not use PVA for any tiling preperation

You need to use a Bal or Mapei tile primer

Something like Primer G from Mapei, This is a synthetic primer and unlike PVA does not reactivate when wet

Agreed!

PVA is a definite no no when tiling. It actually stops the tile adhesive from forming a bond with the plaster.

If any so called "professional" tiler came to my house with any PVA, he'd be out on his !!!!.

phill99

The OP is talking about a floor.

andyhop

phill99 wrote: »

The OP is talking about a floor.

The same applies to the floor, If the screed is cement based and not gypsum there is no need to prime, Just use a fast set cement based adhesive such as Mapei Keraquick

MX5huggy

Don't PVA I don't understand the addiction to to PVA in the trades, Think some pros like to make things just a bit more complicated (expensive). Might as well use milk.

keystone

MX5huggy wrote: »

Don't PVA

+1

I don't understand the addiction to to PVA in the trades, Think some pros like to make things just a bit more complicated (expensive). Might as well use milk.

Plasterers and brickies like PVA. Tilers and PDs hate its very existence. There is no addiction to PVA in the tiling trade so your comment is a rather unsubstantiated generalisation if I might say so.

Cheers