please help what is this? And why?

[elizabeth1985]

hi
we are currently stripping our little box room, 3rd bedroom in a three bed 1930's semi detached house. there was originally lining paper covering this wall, just this wall that is an outside wall. Underneath this we found this grey/ black plastic stuff stuck to the wall with a strong black tar adhesive. The wall feels cold and there was a little mould at the bottom inside some of the lining paper. The lining paper is not damp but feels a little moist or like condensation is around.
Could anyone please help us identify what this is and what is going on here. What is the lining and what is the purpose of this lining.

Any advice would be great thanks

 

[ajstoneservices]

It looks to be bitumen lining paper to stop damp.

EDIT: http://www.gowallpaper.co.uk/doric-anderton-three-in-one-damp-proof-foil-paper-10m.html

 

[elizabeth1985]

thanks for the info. we are worried that this is hiding problem.it very well bonded to the wall which would be very difficult to remove.

 

[sparkwright]

Almost certainly hiding a problem.

Is the wall outside bricks? And if so, is the pointing crumbly?

Any cavity wall insulation?

Any rubble likely to be stuck in cavity?

Usually such problems are put down to condensation, but would be worth checking to see if actual damp is (or was) getting in.

No one puts that bitumen stuff up unless there is or was a problem.