Workforce management technology specialist Biosite teamed-up with the Enquirer to quiz the industry about skills fears.
The results make grim reading as firms confirmed their reliance on EU-labour and highlighted a lack of confidence in a new generation of domestic workers filling vacancies.
The survey revealed that 27% of companies had a site workforce made up of more than half non-British EU migrants.
And 71% of companies said they would struggle to operate without EU workers.
One said bluntly: “If we have no access to EU labour we will not remain in business.”
Another added “Infrastructure projects such as ours on the railway will be hit very hard if EU nationals are discouraged from coming to the UK – this is an avoidable disaster waiting to happen.”
And one firm warned: “We are refusing work on the basis that we will struggle with resources for the work post-Brexit.
“The reduced work force will drive up costs, prolong projects, impact on health and safety of workers because we are losing experience and it will also affect quality of work and the final product.”
The survey also showed that 55% of contractors don’t believe that domestic workers can fill the gaps left by a drop in EU nationals.
One firm said: “UK does not have enough people who are willing to work in the industry/apply themselves to gain the relevant skillset.”
The Government has ignored calls from construction to be made exempt from restrictions on “low-skilled” workers earning less than £30,000 a year.
More than two-thirds of the 400+ firms quizzed in the survey said they did not believe the Government understood the impact of its actions on construction.
But some contractors believe the situation will improve in the long-run.
One said: “Brexit will force the country, and particularly the construction industry, to do what they’ve been able to avoid doing for the last 20 years: invest in, create and promote apprenticeship programmes and decent vocational training schemes for young people.
“The cheap, quick-fix of foreign labour will be finished.
“There will be short-term pain, without a doubt, but where there are threats there are also opportunities.
“UK construction should stop bemoaning the loss of migrant labour and get on with implementing plans for the future immediately to avoid the short-term pain becoming long-term.”
Biosite is developing management tools to help construction businesses get insights into their workforces and supply chains.
Spokesman Nick Hickman said: “Digital transformation has already started to happen across construction, partly in response to the skills shortages and the need to improve productivity.
“Effective human resource management has to be a key part of this modernisation.”
To read a copy of the full report click here