Much of Sif Group's income from 2017 was from the offshore wind sector, with less-and-less business coming from the oil and gas business, according to the company results.
The fall in revenue was due to lower levels of work being outsourced, compared with 2016, the company added.
Sif put the year-on-year fall in Ebitda down to "set-up expenses related to the new assembly plant, inefficiencies related to the coordination of the Roermond and Rotterdam production flows, rearrangement of the Roermond production facilities for base-products... and late arrivals of new rolling and welding equipment".
The company also warned of a quiet second half of 2018 "in case the project for which we recently entered exclusive negotiations does not materialise into a contract".
The plans include a temporary reduction in flexible workers.
Currently, the firm is having to outsource some work due to "high utilisation of production capacity" to avoid late-delivery payments.
In mid-March, Sif Group's CEO Jan Bruggenthijs announced he would not be available for reappointment to the role at the company's AGM in May.
Bruggenthijs has held the role since September 2014. He is standing down for personal reasons.