Construction union UCATT has indicated its surprise at the continued rise in the number of self-employed people working in UK construction despite an attempt to tighten up the amount of casual labour in the industry.

New figures obtained by the union revealed that false self-employment and casualisation grew in the construction industry last year.

A freedom of information request revealed that the number of workers who received payments via the Construction Industry Scheme (CIS) increased last year. The HM Revenue and Customs confirmed that 963,000 workers received payments via CIS in 2014/15 and “this figure will increase later this year as a result of some returns being made late”. This is a 39,000 increase on the 924,000 workers paid via CIS during 2013/14.

The increase in the use of CIS is particularly surprising as in April 2014 the UK government introduced new rules that prevented agencies and other “intermediaries” from employing workers on a self-employed basis. The changes in the rules, which have resulted in hundreds of thousands of workers being forced to operate via umbrella companies, were expected to result in a fall in the number of workers employed via CIS.

Brian Rye, national secretary of UCATT, said: “These figures show the fragmented mess that the construction industry is in. The government’s changes which were meant to reduce false self-employment clearly haven’t worked while at the same time hundreds of thousands of workers are being employed by agencies via umbrella companies.

“It is clear that the only way to resolve the problem is for fundamental change with workers either being classed as employees or being genuinely self-employed in business for themselves. Further tinkering of the rules will just make the situation worse.”

In 2012 UCATT estimated that false self-employment in construction was costing the Exchequer £1.9 billion per annum. The principle beneficiaries are employers who avoided paying £1.2bn in employer’s national insurance contributions.