“The core of our innovation is our hollow wooden module that is designed to be strong enough to maintain a nearly full vacuum inside the module. We use sensors to monitor the measure wood moisture content levels then a vacuum pump to keep the wood material dry at all times,” says Pasi Herranen, co-founder and Chief Technology Officer at the Finnish company VacuumWood.tech.

VacuumWood.tech is a leading company in novel wood construction technology, called VIS, developed at Aalto University, to enable the long-term use of wood as a construction material by continuously monitoring moisture levels in the material and removing excess. This tight control of moisture extends the lifespan of the material and limits the development of mold to maintain good air quality.

Panu and Pasi Herranen in front of the first industrially manufactured VIS module (Credits: Kimmo Syväri)

Moisture control in wood by creating a vacuum
According to the company’s website, VIS technology eliminates possible moisture problems and degradation that typically plague wooden constructions over time. The technology offers enhanced moisture wicking and removal to prevent the biodegradation of wood, guaranteeing that the company’s wood-based structures will last more than 100 years and thus remain an effective carbon sink.

Moisture control is managed using sensors to monitor levels and then a vacuum system to pull excess water out of the material. Briefly, a vacuum pump is plugged into the module when moisture levels rise, triggering the depressurization of the module. Water trapped inside the wooden element begins to boil at the ambient temperature and can then be removed in gaseous form.

“VIS technology makes it possible to use wood as a construction material in moist and humid environments like vertical farms. Most buildings are made of concrete, steel, and plastic which are not very sustainable. Our company offers this sustainable construction element with an extended life cycle,” according to Panu Miettinen, co-founder and Chief Commercialization Officer at the company.

The vision of how the wooden farm would look out in the future with the transparent coating on top of the wooden module frames, no extra credits needed

Pilot facility at Finnish horticultural research facility
VacuumWood.tech has built its pilot facility at the horticultural research facility at the Natural Resources Institute Finland (Luke) in Piikkiö, Finland. The pilot facility has seven modules which each have a maintenance interval of more than two years. This means that vacuum drying is only expected to be needed a few years down the road.

The modules’ wooden frames are coated with a thin layer of aluminum for maximizing the reflection of light inside the vertical farm (and for reaching the airtightness needed for vacuum drying purposes). Also, heat generated by the vertical farm can be easily recaptured due to the structure’s high level of insulation and then reused in adjacent buildings such as greenhouses, commercial spaces, or residential buildings.

The pilot facility (Credits: Kimmo Syväri)

“There is a strong advantage of economies of scale if vertical farms build larger facilities with a higher planting density per floor square as we can then capture more heat as well. This provides another income stream for the vertical farm,” says Panu.

Moving forward, the company wants to further develop its VIS technology for use in commercial and residential buildings. VacuumWood.tech is also exploring the use of a vacuum as insulation as well to further improve the insulation capacity of its structures. Finally, the company is eager to develop partnerships in other countries to facilitate the production and distribution of these modules internationally.

For more information:
Vacuum Wood.Tech
Pasi Herranen, co-founder and CTO
Panu Miettinen, co-founder and CCO