quick question about tiling on ply

[Jrterror]

Hi
I've just laid my hardiebacker down ready for my floor. As advised a short while ago. But I got wondering...is it ok to tile upon plywood (6mm) if you can cover the entire area to be tiled with one sheet of ply with no joins
Is it the joins between sheets that cause the problems?

 

[Waluigi]

No.

The reason we don’t tile onto ply any more is because most ply wood has a very thin top veneer, the glue used to bond the layers together is poor quality and above all it’s not a particularly stable product to tile onto as it moves around the seasons and in humid environments.

Some of this of course is debatable and there are some ply woods that don’t suffer with some of these issues but overall a tile backer board is better plus it gives more rigidity than a ply of the same thickness.

 

[Jrterror]

Hi Waluigi
Thanks for your detailed answer. Very interesting actually.
Learning everyday.
Thanks again

 

[acaciaguy]

Don’t use ply use backer board for the reasons stated above.

On a similar note I believe British standards were updated this year to say tiling onto ply on walls is now a no no. I can’t imagine doing that anyway but it’s been updated. I don’t think The update explicitly mentions floors with ply but the reasons given apply to both areas and echo Waluigi’s connent.

 

[Waluigi]

Chipboard is fine tho...... with an S2

 

[Waluigi]

Was only kidding

Pic to prove it

 

[acaciaguy]

Chipboard is fine tho...... with an S2

View attachment 101494

And lots of pva lol

 

[Jrterror]

Hi. Are there any pointers for tiling the floor. Is it basically the same as walls?

Specifically, should I be aiming for minimum thickness of adhesive? The tiles are 450 X 450 and 7mm thick.

What do I do with the joints between the Hardi backer. I've not done owt with the joints yet.

Thanks everyone for your input
D

 

[Waluigi]

2mm gap, self adhesive fiba-tape. Skim the joint with adhesive.

 

[Glynn]

No.

The reason we don’t tile onto ply any more is because most ply wood has a very thin top veneer, the glue used to bond the layers together is poor quality and above all it’s not a particularly stable product to tile onto as it moves around the seasons and in humid environments.

Some of this of course is debatable and there are some ply woods that don’t suffer with some of these issues but overall a tile backer board is better plus it gives more rigidity than a ply of the same thickness.

Waluigi is right with this but please don't get to hung up with tiling or not to ply-wood. It has been tiled to for many years without problem when installed in the correct areas. It is the installation in "humid environments" that are the problem. Yes backer boards are more stable in these environments but the correct grades of ply-wood will allow you to do a lasting tiling installation without problem. The older tilers on this forum will remember when ply-wood was all you could use, and it didn't cause issues, it is only recently that ply-wood has deteriated in quality and it is this ply-wood that is the issue. At Tilemaster all our flexible adhesives and levelling compounds are suitable onto "flooring grade Class 3 or Hansons SP101 ply-wood" Hansons SP101 is used in our lab every day for testing products and this is because of its stability and superior quality. The soft flooring industry only use 6mm ply-wood when over laying a floor and pour levelling compounds on them without any issuse.We at Tilemaster do not have any plans to remove ply-wood from our list of suitable substrates to be tiled to so long as the main substrate meets the BS5385 standard for strength and stability and the correct ply-wood is used. BS5385 also says to "consult with induvidual manufactures for thier recommendations".

"For the purposes of this British Standard “normal conditions” means normal environmental temperatures and humidity. However, it is not to be inferred from this that all recommendations made
in this British Standard are unsuitable for more extreme conditions. Manufacturers’ instructions contain limitations of their products."

It is this knowledge of "our" products why we have confidence in where it can and cannot be used.