Floating floor will you or won't you - Tile Advice

[baht'at]

Hi all.
My first floating floor to tile so seeking advice as read quite a few threads where some will and some won't tile on them.
The work in question is a new extension on a property consisting of 4 rooms 3 of which need tiling in ,with the same tiles in running through all of them.
Kitchen 24sqm
Hall 6.5 Sqm
Cloakroom 4.5 sqm
At the moment this extension is just a block shell with each room sepperated by a single course of blocks which will be the floor level sepperating each area from the next in the door ways.
The customer informed me that the builder will be laying Kingspan and over boarding each room.
(1) My concern with this is should the over boarding run through each door way or stop in the middle of the door way and as there will be block work under the joining point to the next room could there be problems with temperature in these areas.
Originally these floors where to have piped UFH heating but due to gas supply problems for 2 boilers this has had to be changed to electric matting.Which I informed the customer would need covering with SLC even though I have read on here before some don't but I am happier if it is just to protect the cables from the trowel.
I have tiled over UFH before but it has always been a continuous mat and not separate mats.
Each room to be tiled with the UFH will be independently wired and controlled.
(2 ) Would an expansion joint be required between each room as in the door way, as these floors may be operated at different times.
( 3 ). Could antifracture matting be used in the door ways instead of an expansion joint.
Any advice on prep work and the laying of the tiles would be greatly appreciated

 

[Andy Allen]

Personally ....I wouldn't tile a floating floor, to risky imo..

 

[Rookery]

Neither would I.

 

[One Day]

Me neither. I'd rather get a paper round.

 

[baht'at]

Thanks for the replies.
As I thought there would be mixed opinions and the NO's lead at the moment.
Just to add to my original post .
There is a concrete base in each room and would probably take at least 100mm of Kingspan plus 20/25mm tounge and groved boards.
Having read on a few "Tiling advise" sites there are some saying as laid on concrete there would be very little if any movement and to over board with 6mm no more ply would make it all more ridged, and as long as the tounge and grove are glued and also the edges of the no more ply are also glued it should be fine for tiling.
Any views?

 

[One Day]

I know how to effectively stop lateral movement on a floating floor. The reason i won't touch them is the compression of the kingspan. Might not happen for quite a while, but if/when it does, it'll be the Tiler who gets called first.

 

[One Day]

And it's not a lack of faith in kingspan as a product. Rather a total lack of trust in builders to actually prep it all properly. If i could fit everything myself and know there are no loose voids, then I'd also tile it.

 

[baht'at]

Appreciate your answer and understand where your coming from and hadn't given that factor any thought

 

[widler]

But What about the thousands of houses with kingspan or jablight under there concrete floors though? Shirley theres much more weight with concrete on top so thinking logically the concrete floor would compress the kingspan more ?
before now ive fastened down the floor with screws etc , hardied and tiled .

 

[Chalker]

If you fit fermacell flooring on top of the insulation. Instead of chipboard / ply . It will be fine. It's a gypsum product, that is glued and screwed together. True it is a floating floor, but it is stable and you can tile straight to it.
The boards are very heavy .

This link explains it.
Jupiter Systems - Fermacell - http://www.noneedtoscreed.com/fermacell.php

 

[Flintstone]

Recently been through this, tilemaster advise overblarding with 18mm wbp ply, or 12mm hardie /nmp. Then tiling with ultimatel flex.
I didn't do the job but that's what they suggested. I wouldn't go any less spec than that if I was you

 

[Andy Allen]

But What about the thousands of houses with kingspan or jablight under there concrete floors though? Shirley theres much more weight with concrete on top so thinking logically the concrete floor would compress the kingspan more ?
before now ive fastened down the floor with screws etc , hardied and tiled .

I would fill my pants panicking I would hit a water pipe or a lecky cable doing your method...

 

[One Day]

But What about the thousands of houses with kingspan or jablight under there concrete floors though? Shirley theres much more weight with concrete on top so thinking logically the concrete floor would compress the kingspan more ?
before now ive fastened down the floor with screws etc , hardied and tiled .

That's true, but a thick layer of concrete doesn't sag and bend like chipboard. Plus it fills and dips and gaps.

 

[One Day]

And don't call me Shirley, Craig!

 

[hmtiling]

Did one a few months ago with blanke permat and a load of good fibre slc and so far so good.