Metsä Group has built a largely automated kertopuu mill in Äänekoski, producing beam and board materials used in the construction industry. The production process is controlled from a central control room and production data is utilized to improve production efficiency and the quality of the end product.
The factory's first production line will be operational in early 2026, with test runs and technologies tested. Test runs of the second production line are just beginning. The factory is scheduled to start operating in the second half of 2026.
Kerto LVL products, made from softwood veneers, significantly reduce the carbon footprint of buildings compared to many other material options.
Metsä Wood currently also manufactures Kerto LVL products in Lohja and Punkaharju.
Data-driven automation
The technological solutions at the Kerto LVL factory in Äänekoski emphasize automation, energy efficiency and material efficiency. Doing more with less.
“We are talking directly about the utilization ratio. We have a clear goal of getting more product from one cubic meter of logs. We currently use 2,5 cubic meters of logs for one cubic meter of kerto wood. And even that can be improved a little,” Metsä Wood’s project director Eero Lampola says.
Automated, data-driven and resource-efficient production is combined with the use of renewable raw materials. Thanks to its technological solutions, the factory produces consistent building materials that meet the requirements of modern construction and also support the transition towards more sustainable construction.
“What we particularly focus on is dimensional accuracy,” Metsä Wood’s Design Manager Iiro Kapanen points out, referring to Kerto wood as a product with precise dimensions and uniform quality.
This makes the material easier to build and improves the reliability of structures. Kertopuu also does not warp like, for example, regular lumber.
A long project journey to Äänekoski
Eero Lampola and Iiro Kapanen have been involved in the project for a long time. They point out that the factory was considered for several locations before Äänekoski was chosen.
"I first started working on the factory layout in 2018. Although the location and story have changed along the way. But since then, with this job title, I have been exploring the factory, in several locations," Kapanen says.
“We surveyed a total of about ten locations,” continues Lampola, who became involved in the planning of the factory in 2020.
The final investment decision for the mill was made in 2023, with Äänekoski selected as the location. One of the most important reasons for choosing the location was the synergy benefits brought by Metsä Group's Äänekoski mill area.
"The bioproduct mill will help the Kertopuu mill significantly. Firstly, we get energy from the biopower plant and the recovery boiler, which means we didn't have to build the power plant ourselves. Secondly, our by-products such as sawdust and chips go directly to the bioproduct mill and the biopower plant, they don't have to be transported further. Thirdly, Metsä Group still had to identify a suitable land area for our mill." In addition, we benefit from the wood raw material logistics of the mill area, says Lampola Lista.
A factory full of technology
– The factory, which cost 300 million euros, will start operating in late 2026.
– Highly automated production lines. The production chain from log processing to finished Kerto LVL products is under digital control.
– Advanced peeling and drying technology is utilized in the production of veneers.
– Veneer sorting is based on machine vision and measurement technology, which enables precise control of strength properties and optimal use of the material.
– A key technological solution in LVL production is a pressing line, where veneers are glued and pressed under high pressure and temperature.
– The degree of automation is also high in material handling and logistics within the factory. Automated transport systems reduce manual work steps, improve occupational safety and increase production efficiency.
