In 1928, Alvar Aalto won the competition to design the tuberculosis sanatorium to be built at Paimio, Finland. It was one of his first and most important opportunities to differentiate himself from the architecture in vogue at the time. Paimio’s design stands apart from that of many other medical instutions due to Aalto’s attention to detail and his considerations of how the space would be used by its occupants.
The basic layout of the building is of three bars, splayed out at angles to one another and connected at the center. Aalto had seen the same scheme at work in another tuberculosis sanatorium at Zonnestraal, and he adapted it for his design. The first bar contained patient housing and nursing facilities, the second a cafeteria, and the third services. At the time the sanatorium was built, tuberculosis was an incurable disease that was treatable only through sunshine and fresh air. Aalto’s design, therefore, needed to include easy access for all patients to the outdoors. Rather than forcing all the patients to go to the ground floor and go outside to get sun and fresh air, Aalto placed a tower of “suntraps” at the end of the patients wing. This tower is tangentially attached at the corner of the patients’ wing, but angled to face due south, giving the patients as much sun as possible.
The design of the tower is impressive. Aalto wanted the suntrap to have very clean lines and to be reserved for a single purpose, sunning. Accordingly, the space needed to be extremely wide and not very deep, because the sun would not penetrate very far into the space. This creates a massive problem—a suntrap six stories tall is also a giant windtrap. The tower would have to withstand a huge amount of lateral load pushing against a broad wall without much depth to brace it. To counter this, Aalto made the wall extremely massive by making it one giant poured-concrete structure. With each floor the massive pillars get smaller and smaller, giving the building a low center of gravity. This did not provide the needed lateral strength, however, so Aalto designed a massive pyrimidal foundation for the tower that anchors it securely into the ground. Even with all these structural considerations, though, the suntrap tower still appears clean, light, and linear.
There is one quality that a medical building needs to convey above all others—cleanliness. Aalto designed what we would think of today when we think “clean”—simples lines and white surfaces. But unlike many other designers, Aalto went a step further and thought about the impact occupants would have on those white walls, turning them dingy and grey. He realized the amount of work that would need to put into cleaning the walls, work that probably would not happen as often as it needed to. So anywhere hands would likely come into contact with the walls, he made them grey. That way, as many of the surfaces that could stay white did, and those areas that would normally look dirty looked clean.
Aalto’s considerations of how people would use the space went further than simply making predictions. He made an extra effort and actually talked to hospital patients to determine what problems they had with hospital design as it was, and he designed the sanatorium to resolve those issues. Patients told him that when others got up to use the restroom in the night and turned on the sink to wash their hands, the splashing of the water woke them up. Aalto designed sinks that make no noise when water hits them. Patients told him that the heating ducts only heated part of their body. Aalto put radiant heating panels above the patients’ entire bed. Patients told him that fresh air coming in through the window was too cold. Aalto designed windows that let the sun warm the air before it entered the space. The level of concern Aalto had for the patients that would be spending a large part of their lives at the sanatorium shows in his work, and it sets the design of the Paimio Tuburculosis Sanatorium apart from medical buildings of his time and even those built since.