Floor Tile levels - what is the Professional standard?

[ayjayh]

As part of a complete new kitchen I have just had the floor tiled professionally. Before laying the tiles the floor was covered with 6mm marine ply so the tiler was starting from a flat surface.

The tiler is on holiday this week but when he returns I will get him to replace at least four tiles which are not level, i.e there is a step between adjacent tiles which makes it a definite trip hazard.

The worst case is a step of 2mm between tiles but going over the whole floor with a 12 inch steel rule I can find plenty of places where the I can rock the rule.

What standard could I insist on. Is it reasonable for the tiler to defend anything other than perfection? Is there an industry specification?

Any comments welcome, thanks

 

[tictic]

firstly 6mm marine ply overboard is not suitable for fixing tiles to.

as for the lippage i cant comment on, as i cant see it!...wont slag anyone elses work!..

as for the 12" rule again without seeing it cant comment,just out of interset how big are your tile?..

 

[J_N30]

Have you gone over it with a spirt level?

 

[ayjayh]

firstly 6mm marine ply overboard is not suitable for fixing tiles to.

That's a pity, I was assured before the work started that ply was the way to go. Guess it's too late to do anything about that.

as for the lippage i cant comment on, as i cant see it!...wont slag anyone elses work!..

Thanks - another new word for me, and at least I can refer sensibly to the problem now.

as for the 12" rule again without seeing it cant comment,just out of interset how big are your tile?..

The tiles are 600 x 300

 

[ayjayh]

Have you gone over it with a spirt level?

No, the levelling is not the problem, just the "lippage"

Is there a British Standard for lippage?

 

[Richard C]

6mm ply overboard is not thick enough; BS & all quality adhesive manufacturers specify minimum 15mm, however, 12.5mm is regarded as sufficient in most cases but it must be correctly & securely fixed. Marine ply isn’t necessary; WBP uses the same waterproof veneer adhesive but doesn’t have the expensive decorative face veneers which you won’t see anyway.

Lippage depends on both the size & type of tiles your using but, generally, it should not exceed 0.8mm on a 3mm grout line & 1.6mm on a 6mm grout line; personally, I would expect to achieve much better than that. Other factors that could affect lippage are excessive variation in floor level, bow in the tiles & the type of adhesive bed/trowel being used; a large format trowel should be used with tiles that size.

 

[ayjayh]

Thanks everyone for your replies.

It's a pity about the ply thickness but I think it's too late to do anything about it now.
I will be insisting on replacing those tiles which are giving giving a lippage of 1mm (probably replacing 4 or 5 tiles) and will then have to live with the result which overall, apart from the bad places is really very good.

 

[a4drk]

Personally, I use 9mm plywood & have been doing for years.
I've never had a problem... yet - touch wood (no pun intended)

Firstly - what was your wood floor like before ?
If it was chipboard in a relatively new house. If you havent have any bother with movement or water damage - then I guess you probably would get away with 6mm. HOWEVER - depends on a few things.
1) - make sure it was screwed down - 150mm centres. - Ring shank nails come loose - i dont care what anyone else says - they do - fact!
just laziness not to screw it - no excuses nowadays with battery drills.
2) - Was the wood prepped with a bonding agent? - Some flexi adhesives say you dont need to prep it, but you are always best to do so.
3) - Make sure the bloke used a flexi floor adhesive & flexi grout.

as for the tiles not being level - the bloke who done it hasn't taken care in doing it.
he could have easily packed it up to get them level - checking it with a spirt level.

anyway - my 2p's worth
hope this has been of use
Cheers
David

 

[Richard C]

Personally, I use 9mm plywood & have been doing for years.
I've never had a problem... yet - touch wood (no pun intended)

I think you should consider yourself lucky; keep hoping your luck doesn’t run out, when it does it will cost you dearly.

If it was chipboard in a relatively new house. If you havent have any bother with movement or water damage - then I guess you probably would get away with 6mm.

That’s poor advice; chip (crap) board is also the worst possible flooring material you could have as a tile base & I would normally plan to rip it up (even green MR stuff) & replace with 18-25mm WBP ply depending on floor construction.

1) - make sure it was screwed down - 150mm centres. - Ring shank nails come loose - i dont care what anyone else says - they do - fact!
just laziness not to screw it - no excuses nowadays with battery drills.

You right in saying never use nails. The overboard should also be screwed through into the joists not just into the top of the original floor otherwise the new tile base will only be as rigid/secure as the original floor fixings. If you intend only to screw into the surface, provide additional screw fixings on the original flooring first or it could lead to the new floor cupping & tile failure especially if you didn’t seal the back; check for pipes/cables first obviously.

2) - Was the wood prepped with a bonding agent? - Some flexi adhesives say you dont need to prep it, but you are always best to do so.

You should seal the under side & edges of the ply with SBR sealer before laying but should not use a primer/bonding agent on the tile base unless the addy manufacturer recommends; you could cause adhesion problems & invalidate the manufacturers warranty & NEVER use standard PVA on any tile base.

3) - Make sure the bloke used a flexi floor adhesive & flexi grout.

The product use is also a major factor; always use a quality trade adhesive & grout, never cheapo DIY stuff.

The thickness of ply used for overboard or floor replacement is very much dependant on floor joist size/pitch/span which must always be a factor when deciding what to use. I would never use less than 12mm for over boarding but, from choice, I will always replace the floor anyway, 18-25mm WBP, depending on floor joist construction & the use/loading of the area e.g. - light (bathroom) or heavy (kitchen).

Board layout is also a critical factor & should be planned; you shouldn't just do whatever fits easiest or is the most economical in terms of number of boards you need.

 

[a4drk]

If it was chipboard in a relatively new house. If you havent have any bother with movement or water damage - then I guess you probably would get away with 6mm.

That’s poor advice; chip (crap) board is also the worst possible flooring material you could have as a tile base & I would normally plan to rip it up (even green MR stuff) & replace with 18-25mm WBP ply depending on floor construction.

So what you are saying is that if went to someones house to do a tiling job- lets just say its a brand new flat with chipboard floor - and it's in the kitchen.
Chipboard floor is nailed to the joists etc & goes wall to wall under the kitchen units.
What would you do here ?

David

 

[Richard C]

So what you are saying is that if went to someones house to do a tiling job- lets just say its a brand new flat with chipboard floor - and it's in the kitchen. Chipboard floor is nailed to the joists etc & goes wall to wall under the kitchen units.
What would you do here ?

Not sure if this is a genuine question or a “hypothetical dig” but it will obviously depend on individual circumstances . In your case you would obviously make the best of it; overboard with ply or, perhaps, tile backer boards would be a better choice but still probably 12mm in a kitchen. If there is a threshold height problem the customer doesn’t like or I didn't like the look of the floor construction there are still other ways you can tackle it without ripping all the units out but that would be a customer choice/cost decision; gets me off the hook if it goes wrong. Each case is different. I mostly do complete room refurbishment rather than just tile fix so it’s usually not a problem for me as it’s all coming out anyway; do it properly, never any come backs.