Wood as a material for health buildings has raised interest during the past few decades as environmental issues and health-benefiting design strategies focused on natural and renewable building materials. A number of scientific studies has explored the influence of wooden materials on measured and perceived indoor environment quality (IEQ), looking specifically at emissions of chemical compounds, wood’s contribution to the thermal comfort due to its moisture buffering capacity, antibacterial effects, acoustics, and psychological (e.g. human-nature relationship) and physiological effects (e.g. thermal feedback). The field of research on the influence of wooden interior materials on IEQ has been extensively reviewed underlining wood’s great potential as building material in healthcare facilities. However, the review of the scientific work in this field discloses also the knowledge gaps that must filled to safely use wood products to much greater extent than today in interior architecture of buildings with high demands towards surface hygiene. Summarised, the scarce use of wood in healthcare buildings today depends on specific challenges concerning hygiene, chemical and mechanical resistance as well as fire. Due to the lack of updated guidelines, most healthcare organisations, planners, architects and builders stick to traditional solutions with other materials. This aloofness of using wood is found in all countries participating in WOODforHEALTH. In Norway, 13 new hospitals will be built during the next years under the direction of the Norwegian Hospital Construction Agency, which is represented in the advisory board of WOODforHEALTH. At a international seminar on the topic Wood and Health that NTI organised in Oslo in 2019, the agency expressed its desire for extended use of wood due to its environmental assets as well as its positive effects on the psychological welfare and indoor air quality. However, the use of wood in health buildings is sceptically seen mainly due to concerns regarding hygiene. Finland has only two wooden health centres so far but a third one is currently planned in the town of Kuhmo. Like the Norwegian Hospital Construction Agency, the town of Kuhmo wishes an extensive use of wood in the new health center but misses a reliable documentation and guideline. The town of Kuhmo therefore decided to be partner (UOULU) in WOODforHEALTH to discuss opportunities and challenges wood offers. In Latvia, the use of wood materials in public buildings procurements is not obligatory but highly recommended by the Ministry of Economics. However, an extended use of wood in healthcare buildings still seems far-off. A similar situation is found in Germany, which has only very few hospitals with wood in interior architecture, mainly due to hygienic concerns.

Nevertheless, recent examples around Europe show that wood treated appropriately may be used in certain zones of healthcare buildings. One prominent example is Queen Silvia Children’s Hospital in Gothenburg in Sweden, which was designed by the project partner White Arkitekter. According to White, the limiting reasons for not using more wood were related to following aspects:

• Wood is perceived as a surface difficult to clean and and disinfect and thus, promotes hospital acquired infections by cleaning and disinfection.
• Coatings do improve the cleanability but, still, the chemical resistance of most conventional wood coatings is insufficient to withstand recurrent cleaning with antibacterial detergents in many zones of the hospital.
• Polyurethane-based coatings do meet hygienic standards in some zones but are difficult to maintain in terms of repainting as their harmfulness require industrial application or application in isolated areas at the site.
• Especially in highly frequented zones, wood’s softness compared to materials like vinyl (PVC) or linoleum is sceptically seen with respect to scratches and marks. Vinyl and linoleum are however neither renewable nor porous; the latter is the prerequisite for moisture buffering of indoor air.
• Concerns about the dimensional stability of wood products due to climatic variations and the usefulness of wood coatings to reduce swelling and shrinking.
• Concerns about the long-term colour stability of wood products and the usefulness of wood coatings to prevent photo-induced disolouration.
• Concerns about the fire safety.

In summary, promoting the use of wood in healthcare buildings is demanding and requires a holistic approach; it requires to fill knowledge gaps especially regarding hygiene, improve the performance of wood coatings and establish profound documentation and clear guidelines for stakeholders that take heed of wood’s complexity as a natural material and facilitate a knowledge-based use of wood products for specific applications.

WOODforHEALTH addresses all these aspects in a transnational collaboration, providing a European perspective. This is of special importance as criteria, regulations and good practices significantly differ between European countries.