A Professional Consultant Certificate is backed by Professional Indemnity Insurance Policy, Professional Indemnity Insurance claims can only be made as a result of proving negligence, which is very difficult to prove and often result in expensive legal fees, this is why so many lenders do not accept a PCC, on the basis that they give neither the mortgage or the mortgagee real protection, my understanding is also that PCC's are also not FCA regulated. @MJamesW is correct, there are companies dressing up a PCC as a 10 Year Warranty, which it is not and this shouldn't be allowed. There are lots of companies that can provide a Structural Warranty quotation, such as Self Build Zone, Protek, Build Warranty, backed by "A Rated Insurers" that are regulated and have lender approval, maybe also take a look at the reviews online to get a good idea of who you are dealing with before committing the ££s