no ply on floor to be tiled

[smokie899]

hello folks. doing a job for a guy 27sq meters kitchen floor but the guy does not want ply down as it will rise the floor up to much (18mm ply 8mmtile 3mm addy) as there is 4 doors leading in/out of this room.
he wants all floors the same level.
the floorboards are in good order and solid, the only thing i could think off was to check for loose ones and screw down and use flexi addy and grout, is this viable.
ps porcelin tiles.

thanks smokie

[doug boardley]

NO, in a word,even if he accepts full responsibility, it's your reputation on the line!

[grumpygrouter]

27m2 is a big floor, ply would add strength but we can't see what you can see. I would imagine that there will be deflection on a floor that big but if it is solid, you might get away with hardiebacker and fastflex, or similar 2 part adhesive. Would deffo be best to ply out though with that size of floor. Have you considered "No More Ply"? The manufacturer reckons (though not proved) that their system is a full strength replacement for 18mm ply!

[doug boardley]

27m2 is a big floor, ply would add strength but we can't see what you can see. I would imagine that there will be deflection on a floor that big but if it is solid, you might get away with hardiebacker and fastflex, or similar 2 part adhesive. Would deffo be best to ply out though with that size of floor. Have you considered "No More Ply"? The manufacturer reckons (though not proved) that their system is a full strength replacement for 18mm ply!

what thickness is this GG and would it be ok for my chipboard thread? cheers doug

[smokie899]

cheers guys. will check out the no more ply route

[grumpygrouter]

[/i][/b]
what thickness is this GG and would it be ok for my chipboard thread? cheers doug

Doug, it is a 6mm cement based board that is stuck down with some sort of polyurethane adhesive and then screwed with 5 screws per sheet. I have never used it as I can't get it up here, but some guys on here have and swear it is a viable alternative to 18mm ply. Bit sceptical myself, but I am happy to be proved wrong.

[Wylie]

Would 6mm exterior ply well screwed down not work?

[Grace'sDad]

Would 6mm exterior ply well screwed down not work?

Yes, but only as well as an ashtray on a motorbike!

[grumpygrouter]

Would 6mm exterior ply well screwed down not work?

Get yourself a sheet of 6mm ply, rest it lengthwise edge on the floor, hold the top edge as far apart as possible and try bending it with your knee in the middle of the board and see how far it moves!

[whitebeam]

If the floor has no bounce and is solid could'nt you use an uncoupling membrane

[DERBER]

Ya may get away with 12mm ply, only if the t&g is in good nick, otherwise walk, and save ya reputation.....

[Wylie]

Get yourself a sheet of 6mm ply, rest it lengthwise edge on the floor, hold the top edge as far apart as possible and try bending it with your knee in the middle of the board and see how far it moves!

you might make a hoop with it.my thinking was and since thats whats used on top of the chip board floors here,if the tongue and groove is a heavy floor would the 6mm not do the same job to masking the joints?

[doug boardley]

if you put a set square over a piece of t&g Wylie see if you can see daylight, that's a measure of the possible deflection imo

[DERBER]

I would only ever lay 6mm ply onto a chipboard floor and it would have to be a small area at that.

glue and screw 12mm ply down across the run of the t&g floor, screwing edges of board onto ever length of T&g, then every 250mm acros the ply.

[grumpygrouter]

I won't tile on 6mm ply. I think it give potentially more problems than tiling straight on to chipboard with "proper" adhesive. Where's "here"?

[pjc]

tell him to stick em down with silicone that wont raise the floor lol

[kilty55]

dont pci do something called pesoplast or something like that,,only a few mill thick but once its down it strengthens the floor?

[whitebeam]

I have heard of it but don't know if a couple mil would strenghten a floor

[Wylie]

I would only ever lay 6mm ply onto a chipboard floor and it would have to be a small area at that.
Iv'e seen it done with 6mm and screwed every 200mm on chip and 150 on tongue and grove

glue and screw 12mm ply down across the run of the t&g floor, screwing edges of board onto ever length of T&g, then every 250mm acros the ply.

12 mm seems reasonable

[Wylie]

I won't tile on 6mm ply. I think it give potentially more problems than tiling straight on to chipboard with "proper" adhesive.

I'll check this one out thanks

Where's "here"?[/quote]
N Ireland

[pjc]

dont pci do something called pesoplast or something like that,,only a few mill thick but once its down it strengthens the floor?

Yes they do but it doesn't strengthen the floor its a decoupling membrane and its less than a 1mm thick great stuff :Pete

[pjc]

Doug, it is a 6mm cement based board that is stuck down with some sort of polyurethane adhesive and then screwed with 5 screws per sheet. I have never used it as I can't get it up here, but some guys on here have and swear it is a viable alternative to 18mm ply. Bit sceptical myself, but I am happy to be proved wrong.

Gumps if it was that good they would give us details i think don't you lol :Pete

[Daz]

I've used no more ply approx 6 months ago onto chipboard floorboards (customer purchased it and I just fixed it). It was 600 x 300 porcelain in brickbond in a bathroom, only about 6.5m2. I used a spf and all seems fine (touch wood).

[whitebeam]

Yes they do but it doesn't strengthen the floor its a decoupling membrane and its less than a 1mm thick great stuff :Pete

Don't seem to be a lot of information about Pete

[grumpygrouter]

Gumps if it was that good they would give us details i think don't you lol :Pete

I agree Pete. What they say in their literature has not yet been backed up by testing and results available for public consumption. This is why I am a little sceptical.

[CJ]

Here ya go

YouTube - Plastic Ply for tiling wood floors

[tactile]

6mm hardibacker board will defo do the trick. topps tiles sell it. its still about £10 sq mtre mind. but its easy to cut and you dont need to prime it or seal it. great stuff.

[doug boardley]

Here ya go

YouTube - Plastic Ply for tiling wood floors

have seen this stuff before, local stockists are pushing it, but why prime with pva? there's also 5 screwing points in it as well,sounds to good!

[grumpygrouter]

6mm hardibacker board will defo do the trick. topps tiles sell it. its still about £10 sq mtre mind. but its easy to cut and you dont need to prime it or seal it. great stuff.

6mm hardiebacker doesn't add strength to the floor though!

[Oli]

I've has a quick shufty through the no more ply website and it doesnt seem to say anthing about it adding strenght to the floor.

www.nomoreply.com

It seems to be more about getting a good surface to tile onto rather than combatting deflection.