The company was expected to report full-year profits of more than £10m next month.

A trading statement on January 28 said the firm was still on track to hit its targets.

But an announcement yesterday stated: “Following an internal review conducted by the board of Mar City of the application of the company’s accounting policies, it is now expected that the group’s profit before tax for the year ended 31 December 2014, will be approximately £6.3 million.

“The full year results will therefore be substantially below market expectations and not in line with market expectations as announced on 28 January 2015.”

The company blamed the drop on a decision to sell-off 83 Private Rental Sector apartments rather than keep them as investment properties.

Profits were also written-down for the year on two other housing jobs.

The news saw a sharp drop in Mar City’s share price from 97.5p to 44.5p on Tuesday lunchtime.

Mar City operates on sites across the Midlands, London and the South East employing its ground-breaking Modular Method of Construction.