Removing ceramic tiles from plywood

malfunkshun · 11 Oct 2014 at 23:11

unless, of course, it is exterior grade, marine ply or moisture resistant ply......

mattyg · 11 Oct 2014 at 23:15

malfunkshun said:
unless, of course, it is exterior grade, marine ply or moisture resistant ply......

That will still shrink and expand with heat.

Marine ply is very expensive. WBP is NOT marine ply

malfunkshun · 12 Oct 2014 at 00:12

you realise that moisture not heat causes wood to shrink and expand? and that plywood, standard or otherwise, is designed to produce low dimensional fluctuations and that moisture resistant variants are even more stable because the adhesives used result a reduction in the woods ability to absorb moisture so that a product that would usually vary by less than 1% L*W would vary even less.....
Having said all that there are, of course, tile adhesives designed for just this situation anyway.

mattyg · 12 Oct 2014 at 00:26

malfunkshun said:
you realise that moisture not heat causes wood to shrink and expand? and that plywood, standard or otherwise, is designed to produce low dimensional fluctuations and that moisture resistant variants are even more stable because the adhesives used result a reduction in the woods ability to absorb moisture so that a product that would usually vary by less than 1% L*W would vary even less.....
Having said all that there are, of course, tile adhesives designed for just this situation anyway.

But without heat moist wood would stay moist.
I've seen a number of tile installations fail because of the incorrect use of ply. The cost price between ply and sealer/primer and the cost of nomoreply or WEDI is negligible. Not forgetting the thermal advantage of the WEDI board

malfunkshun · 12 Oct 2014 at 01:10

But without heat moist wood would stay moist.
I've seen a number of tile installations fail because of the incorrect use of ply.
[/QUOTE]
But ply isnt wood, it is wood laminate, it has a limited ability to absorb moisture from the outset.
I would wager that the tiles failed because of the use of incorrect adhesives or just a poor job generally.....
Look at the OP here, seems the tiles are a bit of a pig to get off, suggesting that the ply hasn't rotted or delaminated.

mattyg said:
The cost price between ply and sealer/primer and the cost of nomoreply or WEDI is negligible. Not forgetting the thermal advantage of the WEDI board

LOL WEDI board is about 4 times more expensive than dimensionally similar WBP (suitable for this application) and APD for ply, if you wanted to use it but personally I would only seal the board edges before installing them, is less than £20.
No More Ply is similarly priced if you compare it dimensionally but you need the primer and adhesive which pushes it up somewhat, it isn't structural either.
Use the proper adhesive and the correct plywood and there will be no problems.

Anyway, Gilly, I stick to my original thought, pull it down and reboard it, or if that would be a problem board over the top (not ideal).

Kimi · 12 Oct 2014 at 10:52

Reboard. Done this recently and it was a pita, you can get the bits off but for the time and effort it's better to re do

WillyNelson · 12 Oct 2014 at 19:31

Aye, get with yer hammer & rip it off. If your going to do it, might as well do it right.

Gilly · 12 Oct 2014 at 20:54

Thanks all, will show this thread!

Millwall.FC · 12 Oct 2014 at 22:48

malfunkshun said:
But without heat moist wood would stay moist.
I've seen a number of tile installations fail because of the incorrect use of ply.

But ply isnt wood, it is wood laminate, it has a limited ability to absorb moisture from the outset.
I would wager that the tiles failed because of the use of incorrect adhesives or just a poor job generally.....
Look at the OP here, seems the tiles are a bit of a pig to get off, suggesting that the ply hasn't rotted or delaminated.

LOL WEDI board is about 4 times more expensive than dimensionally similar WBP (suitable for this application) and APD for ply, if you wanted to use it but personally I would only seal the board edges before installing them, is less than £20.
No More Ply is similarly priced if you compare it dimensionally but you need the primer and adhesive which pushes it up somewhat, it isn't structural either.
Use the proper adhesive and the correct plywood and there will be no problems.

Anyway, Gilly, I stick to my original thought, pull it down and reboard it, or if that would be a problem board over the top (not ideal).[/QUOTE]

put 18mm WBP over my floor boards then tiled over it 3 years ago never had a problem.

Millwall.FC · 12 Oct 2014 at 22:49

malfunkshun said:
But without heat moist wood would stay moist.
I've seen a number of tile installations fail because of the incorrect use of ply.
But ply isnt wood, it is wood laminate, it has a limited ability to absorb moisture from the outset.
I would wager that the tiles failed because of the use of incorrect adhesives or just a poor job generally.....
Look at the OP here, seems the tiles are a bit of a pig to get off, suggesting that the ply hasn't rotted or delaminated.

LOL WEDI board is about 4 times more expensive than dimensionally similar WBP (suitable for this application) and APD for ply, if you wanted to use it but personally I would only seal the board edges before installing them, is less than £20.
No More Ply is similarly priced if you compare it dimensionally but you need the primer and adhesive which pushes it up somewhat, it isn't structural either.
Use the proper adhesive and the correct plywood and there will be no problems.

Anyway, Gilly, I stick to my original thought, pull it down and reboard it, or if that would be a problem board over the top (not ideal).

put 18mm WBP over my floor boards then tiled over it 3 years ago never had a problem.