Replacing floorboards - do I need a DPM or similar?

[piggeh]

I am currently stripping down my bathroom as there was an old leak before I bought the place that caused the chipboard and some underlying floor battens to rot. When I have removed the battens there was a thin layer of material that felt like paper lying on top of the concrete. On top of this was insulation, and then the chipboards resting on the battens.

Is this (the material between the battens and concrete) a damp proof membrane or something else? Do I need to have something between the battens and the concrete floor to prevent water damage or anything else?

This is in a first floor flat with no external facing walls.

Thank you for any advice.

 

[vinn]

Why not post a couple of photos of the bathroom, & what you have exposed?
Is this a purpose built block of flats such as an ex-council high rise?

 

[piggeh]

This is the floor currently - had the vinyl laid on chipboard, then it was insulation/battens and then concrete floor.

This is the stuff between the concrete and battens.

It feels like a paper, maybe was put in during construction for some reason?

It's a purpose built block of flats but not ex council, only a three storey building of about 20 flats, 80s build I think.

 

[tomfe]

Are the batons fixed to the concrete floor?
80s there should be a dpm below the concrete and all the paper is doing is acting like a slip sheet to help with the thermal movement of the floor.

 

[piggeh]

The battens aren't fixed to the floor, no. I assume that is also to allow movement? So I just need another slip sheet type material if anything at all is needed?

Edit: I read a bit more and they appear to be put in at the time the concrete is drying out, so maybe nothing required now?

 

[tomfe]

Would not worry about it then,they don't get used on modern floors.

 

[piggeh]

Thank you, will plough on without it