We understand if you feel that the moisture-tight course will continue to work after installation to prevent rising damp from reoccurring on your property. Given that they need construction supervisors to be on board with their wet cleaning course, I would say they don't, but hiring professional damp proofing expert is always the best option. Ipswich Damp Proofing 32 Coleridge Rd, Ipswich, IP1 6EL https://www.google.com/maps?cid=14098722535216811698