The new Centralsjukhuset in Karlstad, Nya CSK, is one of Sweden's largest healthcare construction projects. At its heart stands Mottagningshuset – a pioneering building testing new approaches to healthcare architecture – with timber as its guiding principle. Commissioned by Region Värmland and Skanska, White Arkitekter have designed a building aimed at meeting as many of the UN's Sustainable Development Goals as possible.
“Timber can be used as an aesthetic element or as a sustainable material, or, as here: both,” says Cristiana Caira, artistic professor of healthcare architecture at Chalmers, and lead architect at White Arkitekter.
Timber from the region
Värmland is one of the Swedish forest industry's strongholds. Eight per cent of the county's population earn their living from forestry. There is abundant forest here. The timber for Mottagningshuset comes from the region and the structural frame is manufactured at Stora Enso's sawmill in Grums.
“The project is locally produced in the truest sense. If timber hadn't delivered a final product equal to conventional materials, it wouldn't have been used,” explains Jens Axelsson, architect at White Arkitekter.
Mottagningshuset uses a hybrid structural frame in timber and steel. It is optimised to create as much floor area as possible. The columns become more slender higher up the building, and steel beams are used so that floor levels can align with an existing hospital building adjacent.
“We've also made the corridors slightly wider. This allows the technical installations, such as electrical and ventilation systems, to be arranged horizontally rather than stacked vertically,” explains Jens Axelsson.
In two years, outpatient clinics for rheumatology gynaecology and other specialities are expected to move into Sweden's first timber hospital.
“Mottagningshuset is a large healthcare building with day care and outpatient services, even if it isn't the biggest building within Nya CSK. Akuthuset, which will be built at a later stage, covers 90,000 square metres and will house high-tech medical care,” says Jens Axelsson.
“The façade comprises 200,000 reclaimed bricks from Denmark. Internally, there will be timber features in certain public areas. In Akuthuset, the larger new building included in the Nya CSK project, timber will play a more visually prominent role,”says Cristiana Caira.
“We see that timber in hospital environments is becoming increasingly common, precisely because it is aesthetically appealing and provides a warmer feel. Research also shows that visible timber can have a positive effect on patients.
New timber report: Intensive care is possible
The report Hälsa i Trä, produced by RISE, was recently published. Through fictitious design studies they have investigated how timber can be used more extensively in hospital construction. Fire requirements pose no technical barriers, but recommendations for non-combustible materials complicate the use of timber as a structural material. Vibration requirements are also a challenge. This is why Akuthuset, which will house high-tech medical care, will be built with a concrete frame.
“When you have vibration-sensitive equipment such as MRI scanners, plus a helipad on the roof, it isn't suitable to have timber in the structure. Timber technology must develop further before that becomes possible,” says Cristiana Caira.
The report shows, for example, that care functions for intensive care, which have equipment with tight tolerance requirements for building vibrations, can be accommodated if the timber frame is designed accordingly. This opens up possibilities for a greater proportion of timber even in more advanced healthcare buildings than the one being constructed in Mottagnings huset in Karlstad.
“In the report, three different types of high-tech operations were compared, and the results show that it is possible to use hybrid structural frames with timber in both general wards and intensive care units. But operating theatres, which according to Swedish standards need to be at least 60 square metres, are not feasible with current timber construction technology. They require large column-free areas, which leads to spans too great to meet the strict vibration requirements,”says Cristiana Caira, who participated in producing the report.
To increase the use of timber in hospitals, the report proposes that further research and development of materialbased requirements must be converted to performance-based requirements. Likewise, decision-makers and property owners need more knowledge about modern timber construction.
Two international timber hospitals
White Arkitekter are involved in two other high-profile healthcare construction projects that demonstrate how high-tech medical care and timber frames go hand in hand. One is a cancer clinic in Wales, the other a hospital in Tübingen in southern Germany.
“In Wales, they're building multiple buildings horizontally, which of course requires more ground area,”says Cristiana Caira and continues:
“In Tübingen, the hospital is being built vertically. The first storeys have a concrete frame and will house high-tech medical care. On top of that, three storeys with a timber frame are stacked, where there will be wards, and in the patient rooms, timber beams will be visible.“
Policy shows the way
Two years ago, a report from Program för teknisk standard (PTS) suggested that larger hospital buildings in timber are not suitable. One of the greatest obstacles was considered to be fire risk.
“Unfortunately, that has created apprehension in the regions. But in Germany, for example, which is also an EU country, fire requirements look completely different,”says Cristiana Caira.
In Karlstad, the structural frame is clad with plasterboard and surface-treated to meet the stringent fire requirements.
“According to Region Värmland's timber construction strategy, timber should be the first choice for new builds, and it should always be investigated which parts can be built in timber. This political ambition is an important prerequisite for this project,” says Cristiana Caira.
Text: Gustav Schön Photo: White Arkitekter
