Floating floor questions..

[jugglesm]

Hi all, I'm preparing to install a new floating floor on top of an uninsulated concrete slab (which already has a DPM).  I was intending to lay 100mm Kingspan then 18mm chipboard with engineered wood flooring on top.  But this Kingspan guide LINK says I also need to install treated timber battens flush with the insulation at high pressure points (i.e. doorways) and a >250 micron polythene 'slip-sheet' in between the insulation and chipboard.

A couple of questions:

1) The room will be a bedroom/en suite, are battens really necessary to prevent the Kingspan being crushed? Is this required by building regs?

2) Since I already have a DPM in place what is the reason for the polythene slip sheet?

Many thanks for any help

Edited August 10, 2023 by jugglesm

[nod]

No

You don’t need battens But I would use 22 mil chipboard Only 4 mil but will make a massive difference Glue all the joints plenty of wedges around the perimeter 22 mil expansion gap is perfect