The contractor is fully implementing the Site Operating Procedures drawn up by the Construction Leadership Council to ensure staff and subcontractors are not exposed to unnecessary risk of infection.

Additional safety measures include lengthening the working day and resequencing work to allow different workers to be on site at different times and minimise the need for contact.

Operational capacity has been reduced to around 50% by these measures and the enforced absence of workers.

And a key issue is the availability of building materials.

Mark Beard, chairman of Beard, said: “When sites close, that results in a fall in demand for materials, and builders’ merchants shutting their doors.

“This can lead to a vicious circle with more sites being forced to shut, due to a lack of demand for materials.

“In response to the Government’s urgings to carry on working, to honour our commitments to clients, and to keep as many staff and subcontractors in productive work as possible, we are determined to do our bit to help turn the current vicious circle into a virtuous cycle.

“The safety of all those working for us, and of the general public, is always our top priority.

“We are doing everything we can to ensure our sites are as safe as possible, and we will never put pressure on anybody to work on-site when they should be self-isolating.

“We respect other firms’ decision to close sites, but the Government has given the industry a clear steer that it wants construction work to continue where possible.

“We are putting in every possible measure to follow this steer and continue to operate as many sites as we can.”

Mark Angus, managing director of Beard subcontractor Marlin Building Services said: “We are currently working with Beard and have been so impressed by the efforts they have gone to to ensure the site is clean.

“A full time cleaner is on our site sanitising tower scaffolds and hand rails while toilets are cleaned hourly and the workers are segregated and travel separately.

“The site is like a medical centre despite being a building site. My guys have been really impressed with how seriously Beard are treating the situation.”