I want to do this job properly ...

[Gazzer]

How much height have to play with ? Is the concrete down and does the new floor need to meet another floor ???

 

[simon1]

50mm is probably the lowest you can go with a sand & cement screed

 

[White Room]

If your mixing it yourself you can go as low 6mm with ronacrete sbr and a fine sand on concrete base but standard sharp sand/cement would about 50mm.

On insulation minimum is 65mm

 

[Unregistered]

There was going to be 18mm chipboard on the insulation. There would be problems if I had a screed a lot more than that, the door will open inwards and there could be clearance problems. Supposing I can go up to about 25 to 30mm screed on top of the insulation, what product(s) would suitable?

 

[The D]

Mapei do a screed that can go 75mm to 20mm but it has to go on to the concrete if it is 20mm and it can be tiled the next day

 

[Bartlett]

Ha ha, this forum cracks me up. Have read each post in this from the start.....

Ditto
Double ditto :lol:
Triple ditto :lol:
Quadruple ditto etc etc.............. :lol:
Whatever comes after quadruple ditto :lol:

And then the reply...........

OK, I get the message - FLOATING FLOOR BAD THING.
No harm done, it hasn't been laid yet.
So, concrete floor, DPC, 25mm of insulation board, then what?
Umm .... Thanks for the replies, no, really, I do mean it! Like I say, I want a proper job!

:lol: :lol: :lol:

Ps. agree with everyone else; screed it!

 

[simon1]

It is possible to go lower, my screeder woul use a sand / cement mixed slightly wetter incorporating it with a latex additive

 

[merlecollins]

this forum cracks me up

You need Ditra matting then mate

 

[Unregistered]

The builder has agreed to lay a 18mm screed floor instead of the chipboard.
A big thanks to everybody who offered advice on this - it has saved me from having a big problem.