This is a concern my building officer has brought up in his latest letter, could someone advise on this subject? :(
Considerable concern is expressed regarding the tanking provisions provided to the external walls, the membrane sheet has not been fixed in accordance with any manufacturers details and appears to have been fixed to an insulation board in the cavity which is not an acceptable detail. Tanking must be a continuous fully supported fixed barrier with full continuity maintained. The work does not appear to meet the minimum requirements of the building regulations and cannot be approved by building control. A also note that drainage from the proposed ground floor bathroom will penetrate the tanking, any penetrations must be carefully detailed to prevent damp penetration. I strongly suggest that you seek specialist advice and seek a way forward on this matter. I strongly advise against proceeding with any finishing/ plastering work before this matter has been resolved.