The Property Care Association is urging householders to be vigilant to the problem of unauthorised contractors using its logo.
Last year the PCA had 32 reported cases of logo abuse and 17 cases to date in 2012.
Steve Hodgson, general manager of the PCA, said: “As a well-established and recognised trade association, it is only natural that many companies aspire to join us, but some unscrupulous people and organisations try to do so without undergoing our strict criteria for membership.
“It is important the public is aware of logo abusers. If a member is not listed on our website then they are not part of the Association. Alternatively, if there is any doubt, members of the public should not hesitate to contact us and we will be happy to confirm a company’s membership to them.”
The PCA represents the UK’s building preservation industry, working within the structural waterproofing, wood preservation, damp-proofing, flood remediation, invasive weed control and structural repair sectors.
PCA members are also able to carry out specialist surveys as part of the house-buying procedure – to identify potential problems.
The PCA is also a member of TrustMark, the government-backed scheme which aims to help consumers find reliable and trustworthy tradesmen when making improvements or repairs to their homes.
Hodgson, added: “When choosing a member of the PCA, consumers can be certain that they have undergone rigorous, ongoing checks to achieve and retain membership.
“An expert assessor with a wealth of experience and technical knowledge has audited every member and checked the quality of their work on site, carrying out comprehensive technical, financial and operational verification visits.
“As a result all members are qualified and operate within established companies – and are able to offer high quality service and peace of mind that can be supported by independently insured guarantees.”
