Canadian group Norbord said the cash injection will almost double the production capacity at its Murrayhill plant, which was the first in Europe to manufacture oriented strand board (OSB).
The investment is being supported with a development grant from Highlands & Islands Enterprise of up to €15m (£11.5m).
Karl Morris, managing director of Norbord Europe, said: “Demand for OSB is increasing rapidly and this investment will ensure we can continue to meet customers’ needs and remain at the forefront of the European industry.
“With direct road, rail and port access, the reinvested mill will be in an even better position to efficiently serve our customers across the UK and in continental Europe. This investment underscores Norbord’s long-term commitment to Inverness and the Highlands region, and we look forward to continuing to play an important role in the community.”
Norbord expects the expanded mill to come online in the second half of next year, with no disruption to production in the meantime.
Alex Paterson, chief executive of Highlands & Islands Enterprise, said: “We have been working very closely with Norbord on their development plans and are delighted to be supporting the company to invest so substantially in its Highland base.
“This development will put Norbord’s Inverness plant on a sustainable footing for decades to come, and is a huge vote of confidence in the company’s Scottish workforce.”
He added: “It’s worth noting that the positive impact of today’s announcement will be felt well beyond Inverness and the Inner Moray Firth. Norbord is not only a significant local employer in its own right, it also plays an important strategic role in the region’s forestry sector and is a major user of haulage companies and port infrastructure.”
In addition to OSB, which is also used in making furniture, Toronto-listed Norbord produces particleboard and medium-density fibreboard. The firm employs about 2,600 people at 17 plants across Canada, Europe and the US.