It is the third profit warning this year from the firm which has seen its share price halve during the last six months.
Van Elle said profitability in the second half of the year to April 30 2019 was “impacted by end-market volatility and project slippages.”
As a result, the board had expected to report adjusted profit before taxation of slightly over £5m.
Van Elle said: “However, as part of the year end process, the board has determined it necessary to adjust a small number of specific balance sheet items and contract accruals.
“Whilst the results remain subject to completion of the audit, these adjustments will adversely impact FY2019 adjusted profit before taxation by a total of c.£0.5m.”
The company also warned about prospects for the coming year.
It said: “It should be noted that, despite the encouraging momentum at the end of last year, the group is continuing to experience customer uncertainty in some of its markets, resulting in a quiet start to the year in some segments and increased volatility in month on month performance.”
“As set out in April, the group has been successful in securing positions on attractive, long term contracts.
“Although the company is seeing the benefits of a number of commercial and operational initiatives recently implemented, the Board is mindful that market uncertainty and the resultant volatility may persist further into the current financial year, which would limit the rate at which progress can be made.”
Three board directors have recently left the business amid ongoing restructuring by new chief executive Mark Cutler.