Help needed - Cave House

[randelld]

Hi all,
I've searched the forums but cannot find a solution to my particular problem.
I am working on a cave house with serious damp issues. Rain water was penetrating from above as the property was now sealed correctly from
above. I have since sealed it a couple of months ago and have had dehumidifiers in there since. The walls have no exterior, the house is carved into a hillside. The plaster in a few of the rooms is flaking badly and there is a lot of efflorescence coming through the plaster.
I've taken off a bit of the plaster to find that there is about an inch of plaster applied directly to the stone into which the rooms have been carved.
I am currently installing a heat exchange system to replace the air inside the property.
My problem is I need to remove the plaster in the affected areas but am a little stuck as to what to use to seal the rock face before re-plastering in order to stop the efflorescence from coming through and flaking the paint.
Any ideas appreciated

[stoneyboy]

randelld,
I don't think you will have any success with a direct applied system, you will have to fit an air gap membrane system with drainage pump. Look at the projects under TANKING.
END

[randelld]

Unfortunately that type of tanking is not really an option because:
The actual rooms are very small and arch shaped with curved ceilings.

The original construction was simply not done correctly and I would very much like to put it right for them.

Any other suggestions?

[TheDoctor5]

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