So many tilers...So many contradictions.......

[Dazzle1980]

Hi everybody,

I'm getting my hallway and kitchen tiled with porcelain tiles. I've pulled up the old laminate and underneath are just normal wooden floorboards.

We've had quite a few tilers in to quote and tell us what they're do. They've all said that they need to lay ply onto the floorboards, but the ply thickness has ranged from 3mm to 12mm. The tiler who said 12mm sai that he wouldn't want to tile on anything less but he's the only one who's suggested that. 2 tilers said 6mm with no hesitation and the last one that came today said he would lay 3mm!!

Obviously the tiles are quite brittle (being porcelain and all) but ideally id want the tile to be laid on as thin a ply as possible.

What are your professional opinions?

Thanks for you time

 

[mattysupra]

depends on how much flex is in subfloor. I would go with th the guy who suggested 12mm plywood.

 

[mountford]

It depends on the condition of the floor boards, if they are in good condition then you could go on with a product called fast flex BAL product 2 part rapidset flex dunlop product ( this product is the most flexible adhesive you can get it is made from crused rubber tyres and the you add a liquid latex to it) which means there is no raising with the ply. If they are in bad condition then you need to go down with the ply and I always suggest 15-18mm but thats my opion British standards again.

 

[Dazzle1980]

hi thanks for your advice.

The floorboards are in good condition and ill screw them down with additional screws to ensure theyre down tight.

The tyre advhesive that you mentioned....is that rouhgly the same as normal adhesive or much more expensive?

Could you also tell me what would happen if he does lay 6mm ply and it is too thin?

Thanks

 

[Top Tiler]

hi thanks for your advice.

The floorboards are in good condition and ill screw them down with additional screws to ensure theyre down tight.

The tyre advhesive that you mentioned....is that rouhgly the same as normal adhesive or much more expensive?

Could you also tell me what would happen if he does lay 6mm ply and it is too thin?

Thanks

Hi,
The only tiler who knows what he is on about is the guy who said 12mm it must be MIN 12MM and the adhesive must be flexi and suitable for porc tiles also flexi grout more expensive but unless ALL of the above is followed the floor will in time DEF FAIL (tiles crack etc) .
I hope this helps

 

[gcol]

Again, 12mm min. Forget the Bal fast flex - it costs a fortune. Have a look at the sticky.

 

[bananaspark]

get one of them spirit levels with a laser pointer, place it on the floor at vaious points [propped up both ends with coins] and invite some riverdancers round for a jig.

If you cant see more than half a cm deflection in the point from 5 metres away, i'd go with 3mm.

b/

 

[gcol]

If you're joking, seek help.
If you're serious about using 3mm then you're giving out bad advice.

 

[bananaspark]

the thickness of the ply should be proprtional to the integrity of the subfloor, which is where a bit of common sense and a laser comes in.

you wont need any plywood at all on some very well laid and supported wooden floors.

bert.

 

[gcol]

the thickness of the ply should be proprtional to the integrity of the subfloor, which is where a bit of common sense and a laser comes in.

you wont need any plywood at all on some very well laid and supported wooden floors.

bert.

Say what you see.

 

[bananaspark]

I couldnt agree more, golfballs are a fantastic example of how the accepted wisdom of the day was usurped by accident observation and experimentation. [development of the pitted surface]

however i fear your dogmatic approach to tiling may needlessly trip this guy up when he walks into his kitchen next.

b.

 

[gcol]

I couldnt agree more, golfballs are a fantastic example of how the accepted wisdom of the day was usurped by accident observation and experimentation. [development of the pitted surface]

Very good.

however i fear your dogmatic approach to tiling may needlessly trip this guy up when he walks into his kitchen next.

b.

I take exception to the word "dogmatic" and I don't really see that an extra 9mm (3mm to 12mm) would make that much of a step. 3mm ply has very little rigidity to it and to be honest 6mm doesn't either. 9mm is the absolute minimum I would ever entertain using and the floor would have to be very good for me to use it. For the purposes of this forum it's safer in the long run to recommend 12mm. Hell, Bal recommend 15mm minimum for overboarding!

 

[NickStone]

Could you also tell me what would happen if he does lay 6mm ply and it is too thin?
Thanks

The grout will crack in between the tiles. The tiles could come loose and then you'll have the devil of a job fixing them back in. This happened to me three days after the tiles had been laid by a professional tiler. He came back and redid it using flexible grout but the cracks were there until I sold the house.

 

[Top Tiler]

agree with nickstone,gcol min 12mm

 

[bananaspark]

Then it's obvious that you should be working in construction, and not advising on more demanding jobs.

Assume 12mm ply at 11 quid a sqm (wickes price), and say you get 2.5 sqm out of the fastflex 2 part kit -

option 1) 27 quid on ply, plus 4-5 quid /sqm for adhesive = somewhere under 40 quid for 2.5 sqm tiling.

option 2) (if floor passes my test ) 52 quid for 2.5 sqm fastflex, and a few pennies more for a decent ultraflex grout (which you should use on wooden floors regardless).

Given that the punter has the wonga for porcelain and the good taste not to want a step if avoidable, what makes you think he aint gonna shell out 150 -200 quid extra per room so that his manor dont look botched?

b.