Nearly 90% of home owners carrying out work at their property do not ask builders for a written contract, according to the Federation of Master Builders (FMB).
New research has revealed an "alarming number" of consumers don't ask their builders for essentials such as a contract or references when embarking upon a major piece of building work.
While 80% of builders report most consumers do not ask for an agreed payment schedule, less than 10% said clients normally request to see vital insurance policies such as public liability or employer's liability insurance.
In addition, more than 40% of firms needs at least four months' notice from customers who want to hire their services.
Brian Berry, Chief Executive of the FMB, said home owners should be wary of cowboy builders.
"If a builder is free to start work tomorrow, alarm bells should ring," he said.
"Demand for building work is incredibly high at the moment and it should be no surprise that almost one in two builders need to be contacted at least four months in advance of when a client is looking to start a home improvement project.
"The workloads of builders have been rising steadily over the past two years and there's no shortage of work. That's why we're urging home owners who are keen to crack on with their build or renovation projects to start getting in touch with prospective builders as soon as possible."
Mr Berry continued: "There are also indications that home owners are leaving themselves vulnerable to problems in terms of how they approach their building work. The vast majority of builders say that most clients fail to ask for references and even fewer ask for a written contract on their work. There is a similar trend when it comes to asking for critical things like an agreed payment schedule and key warranties on work, as well as checking whether the builder has any external accreditation or recognition from professional trade association like the FMB.
"These protections really are essential to helping clients weed out the cowboys and mitigate against any issues that could crop up during the build. A quality builder will insist on these things and if they don't, consumers ought to question why."
(LM)
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