Tiling Standards (BS 5385) | British Wall and Floor Tiling Standards - IN FULL

[Old Mod]

Interesting conversation!

 

[Lee daykin]

hi., first time on here,
But thought I’d give it a go.!
I’m trying to find clarification as to who is responsible for tiling to floors within nhbc standards on site.
We have major issues with uneven floors/screeds.
We have the groundworkers insisting they are laid tolerance, and we have our 3mm at each end of a 2m straight edge tolerance when tiling.
There is a grey are In between the two., as to who is responsible to Make the screed flat to tile to., and indeed whether tiles should be laid to level., or laid to flat.
The screeds are allowed a tolerance of 25 mm out of level over 6 m., which begs the question if we lay level to that maximum tolerance, who is responsible for extra costs involved.
This way also throws up issues at doorways if one end of the house is 25mm higher than the other.
Any bonefide nhbc info would be greatly accepted!!
Thanks lee

 

[LM]

The builder is supposed to provide you with a floor fit for tiling, within standards. If it’s not then you should ask him to correct it by either grinding down high spots or levelling low points or in most cases both. If he doesn’t want to do it then he should pay you to do it. If not then walk imo. Begin as you mean to go on, if you start tiling sub standard screeds he’ll expect you to do the same on every other floor.

 

[Lee daykin]

Hi lee thanks for your reply.
Generally the builders pay us to level the floors. Which we do with a 3m straight Edge and staff it off of the highest points, filling in the dips. Then tile to our 2m +\- 3mm tolerance
The argument now is that we do this to flat and not level. If we went to level, we could have steps at doorways., unless we level the entire house which is obviously not an option.
I guess what I’m looking for is clarification over the level or flat debate.! The is issue on this occasion is that they now want the hallway tiled after having tiled the kitchen to flat., the hallway has a hump
In it, and they’re trying to put it on us that if the floor was tiled to level the jump would not be an issue.
However there would have been a step at the doorway originally. Hope this all makes sense!
Thanks

 

[LM]

When the screed is installed it has three datums that it has to meet which should all be the same, the exterior door sills, the bottom of the interior door frames and the bottom of the stairs. If the screed is meeting all these points then it can't be too far out and if it isn't then there's going to be major issues. If the floor is so far out in the hall the front door probably wont open and the bottom riser height of the stair will be out of acceptable limits for building control. If it's that bad have them take it out and replace it.

 

[Ajax123]

are you talking screed or concrete.

Surely levelling the floor is a contractual issue.

As you rightly say flat and level are different things. I would think flat is more important than level if there is only 25mm fall over 6m.

The screed standards and the concrete standards are generally not very explicit about specific requirements for flatness or levelness. But the contractor will presumably have a specification for the concrete and you will have a specification for the tiling requirements which should be explicit.

 

[Lee daykin]

Yes these are supposed powerfloated screeds., for bovis, Redrow.. laid at slab before walls erected.
it’s a common issue where we are., the nhbc spec is very vague regarding tiling.. (as always).
Trouble is they’re getting ground workers to lay Screeds!

 

[LM]

If I were you and you didn’t want to ditch the job then I’d just charge for my pain. I’m well experienced at dealing with pathetic floors (@John Benton) I’ll do what I have to so long as it makes financial sense. Sooner or later the QS will realise that it’s cheaper to employ professional Screeder’s to do the job properly than to pay you to sort out bad screeds.

 

[John Benton]

If I were you and you didn’t want to ditch the job then I’d just charge for my pain. I’m well experienced at dealing with pathetic floors (@John Benton) I’ll do what I have to so long as it makes financial sense. Sooner or later the QS will realise that it’s cheaper to employ professional Screeder’s to do the job properly than to pay you to sort out bad screeds.

More like ploughed fields Lee

 

[Lee daykin]

Hi gents..
So after a day of emails and phone calls for future reference.
I have it from the horses mouth that is our local nhbc inspector..
screeds are allowed a tolerance of 25mm over 6m, or 4mm per m.
As w knew, and the tolerance for tiling is -/+ 3mm over a 2m srraight edge.
Straight edge being the key word. Not level.
So if the kitchen for example is laid to flat, and then the hallway or any adjoing Room needs tiling as an afterthought., any undulations in that are are treated as a separate entity, and need grinding down/levelling to suit..
thanks for all the reply’s., so kind as someone else is covering the costs then all good.!!
Cheers lee