Floor tiles - how level is level?

[Jeff]

Hi

Strictly not a d-i-y question I guess, but I figure you guys may have some useful advice.

We're in the middle of a bathroom re-fit. The walls are tiled except for the bottom row and the ceramic floor tiling has just been 'completed' We're now waiting for our contractor to return to finish the tiling and fit the sanitary ware. The problem is the floor does not appear to be level by spirit-level or by eye. The contractor has already replaced and over-boarded the existing flooring (which he claimed was 'goosed') so I can't really see any reason why he couldn't get the ceramic floor tiles perfectly level.

So my question is; how much fall across a 4' stretch of tiles is acceptable? Also, how much difficulty would there be in lifting and refitting the tiles? My guess is that it would be almost impossible to remove the tiles intact, but that just getting them off and going back to the board shouldn't be an enormous problem. I'm guessing that removing adhesive from plywood is at least as easy as getting it off masonary.

Many thanks for any advice.

Jeff

[Roger Mills]

Is it a 'wet' room? Does it need a slope in order to drain properly?

If not, then it should be level. I don't know what the official definition of 'level' is - but I would use something like "horizontal within 1mm per meter". If you can detect a slope on a long (3' or more) spirit level, then it ain't level!

Can't comment on the ease or otherwise of re-laying the floor - but I would expect the contractor to resist by all possible means - so you may have to get very assertive!

[Jeff]

No, it's not a wet-room, just a regular bathroom/toilet

Thanks - I'm measuring a fall of 10+ mm over 4' !

Yes, I expect you're right. One problem is that the young chap doing the work has been really thorough in other areas and has done a first rate job generally. As a result he's now under some pressure from his boss to get the job wrapped up. I really don;t like to drop him in it but it looks like I'm going to have to :-(

Thanks again Jeff

[Stuart Noble]

I don't think you can expect to get your floor levelled as part of a tiling job. He lays the tiles flat on whatever surface he's presented with. Otherwise he could get involved with all kinds of secondary problems, possibly structural. As long as the fixtures are level, there shouldn't be a problem.

[Jeff]

Yes, but bear in mind that I'm being charged for re-flooring as well as over-boarding and tiling. I think that if it looks sloping to the naked eye then it's unacceptable. Ensuring that the fixtures are vertical is probably going to make the slope more noticable still.

Surely it's possible to take up a certain amount of underlying slope (and I don't really believe there is any such slope) by varying the thickness of adhesive or by first applying a screed. Maybe I should add that the bathroom is on the first floor of a 30 year old house and all adjacent floors (measured through carpet) appear perfectly level.

Jeff

[daddyfreddy]

If it's seriously sloping to the eye then your joists would have to be levelled. You can't slap on that much tile adhesive to correct it. The floor must have been sloping before this renovation. Unless the contractor specifically said they would correct the slope I don't think there is much you can do. It might be that you're noticing the slope more than anyone else. Unless when walking on it you really feel it, I wouldn't worry about it. You will rarely find a floor that is spirit level.

Also, sanitary ware is not exactly square so don't worry about that. Plus a bead of silicone can be applied along the edge.

[John Rumm]

Which in the grand scheme of things is not actually that much. The problem is that tiled walls will make it look far more obvious than it was before.

They will probably argue that levelling the floor was not part of the job. The difference you have is too much to correct with more adhesive. Ideally you would start by taking up the existing floor, packing out the joists and relaying and over boarding (or just laying thicker ply in place of the boards).

The easiest solution now would probably be self levelling over the new tiles and then a re-tile, but that could give you problems with the change in floor level into the room.

[Stuart Noble]

In that case I'd say there's no excuse for it not being level.

[George]

over-boarded

If you put a rubber ball on one side of the room...does it roll to the other side?

No doubt if it is unlevel then that would be down to the joist in the first place?

[Ed Sirett]

Much depends on what's the root cause of the slope. If the house has settled (quite plausible) and the joist are 10mm out then fixing that is going to be very hard and may lead to a less solid job. I.e A small slope on a solid, smooth floor is better than a flat floor which is less rigid does not match the floor outside the room, cracks the tiles etc...

If the slope is because the laying of the plywood has been haphazard then it really is not good enough.

[Jeff]

Yes, a rubber ball rolls rapidly across to one side.

Mind you, I was at a pub called the "Crooked House" not so long ago and it was clear that things can look level but be far from actually level. They supply golf balls in that pub and you can watch them merrily roll uphill - and that's before you've had a pint!

I don't buy this explanation because a spirit level shows the adjacent rooms (some of whose floors share the same joists) to be perfectly level. And in general all of the upstairs rooms seem level - the house is only 30 years' old.

Jeff

[Jeff]

Thanks.

I suspect a combination of poor over-boarding and adhesive thickness. The house is half-rendered. I think that the amount of settlement needed to produce a 12mm fall across 4' would be more than enough to produce noticable cracks in the rendering. I've also checked all of the other upstairs rooms with a spirit level (admittedly through carpet) and they seem perfectly level - a rubber ball shows no sign of rolling.

Jeff

[Grimly Curmudgeon]

We were somewhere around Barstow, on the edge of the desert, when the drugs began to take hold. I remember "Jeff" saying something like:

I'd get it fixed if it's getting that bad in a few hours.

[Jeff]

Thanks for the concern Dave. No need to worry though, 10+ is just shorthand for a bit more than 10 (e.g.

12).

Jeff

[The Natural Philosopher]

I've corrected over an inch and a half with adhesive.

And there's the rub..ive got a threshshold that steps down an inch and a half into the adjoining room..

Building is not exact, and some builders are less exact than others..you have to decide whether a sloping floor is preferable to a step..