Tuberculosis and Solar Architecture (part 2)

As I mentioned earlier in Tuberculosis and Solar Architecture (part 1), I had written a chapter on sun-responsive architecture of the 1920s and 30s, but it needed to be cut from the book during editing for length.  Here's another excerpt.

I argue that the 20th-century solar house, defined by experimental attention to space heating and energy savings, occupies a different historical space than a strain of sun-responsive architecture in the 1920s and 30s which accommodated sunlight for reasons of health and hygiene (heliotherapy).  This genre, which may be known as heliotherapeutic architecture, emerged in concert with the sanatorium movement in late-19th century Europe, prompted by the idea that sunlight and fresh air contributed to a ‘cure’ for tuberculosis. 

Les Frênes (Leysin, Switzerland, 1911) was probably the first large purpose-built heliotherapy clinic to be constructed.  It featured south-facing rooms with terraces and large windows.  (These early sanatoriums are sometimes called the ‘Davos-type’, as that city was another center of activity.)  The director of Les Frênes, Dr. Auguste Rollier, published La Cure de Soleil in 1914 and L’Heliotherapie in 1923.  The latter became a best-selling book and may have influenced architects such as Le Corbusier. 

The sun played a central but underreported role in some canonical works of early modernism.  Tony Garnier’s Une Cité Industrielle (1901-17) project is well-known for its functional planning innovations and its aesthetic of repetitive concrete cubes, but it may also be interpreted as a “solar utopia.” 

Garnier’s plan included a centre d’héliothérapie, a long building consisting primarily of repetitive rooms with balconies and glass walls behind.  It became a strong influence for the sanatorium architecture that followed.  Garnier’s larger vision included houses that were “planned with equal solar access and … spaced to prevent shading of adjacent buildings during the winter months.”  Public buildings were also designed to receive direct sunlight “for sanitation.”

The most compelling early expression of heliotherapy in architecture is the Zonnestraal Tuberculosis Sanatorium by Johannes Duiker and Bernard Bijvoet (Hilversum, The Netherlands, 1925-31).  Zonnestraal, which translates as ‘sunbeam’, rendered the provision of sunlight and fresh air in the architectural language of high modernism, where literal and figurative cleanliness converged.  Duiker spoke of his architectural aspirations in terms of “spiritual economy.”  In Paul Overy’s view, “Light, air and openness could not have been more generously, or more spectacularly provided.”  This was roughly a decade before any architectural interest in solar space heating.

Zonnestraal Tuberculosis Sanatorium

Zonnestraal Tuberculosis Sanatorium

Attention to heliotherapy prompted some designers towards integration of the architecture and engineering disciplines.  Zonnestraal’s award-winning restoration architect Wessel de Jonge has explained that Duiker and Bijvoet “preferred to coin themselves building engineers rather than designers, as proper knowledge of heating and cooling systems was decisive in designing light, open plan or even semi-open-air buildings for [the] climate.”  The concept of the architect as ‘building engineer’ also became significant theme in the history of the solar house. 

Duiker continued along this path of engineering innovation by using radiant ceiling panels in the Open Air School (Amsterdam, 1927-28), and patenting a hot-air system for the Gooiland Hotel (Hilversum, 1934).  It is striking to note that European architects conducted most of the exploratory work in heliotherapeutic architecture, while the solar house was principally an American phenomenon in its early experimental period.   

The deep sympathies between modern medicine, modern architecture, and the sun are further demonstrated by Alvar Aalto’s tuberculosis sanatorium at Paimio (1929-33).  The line of influence here is quite direct; Aalto had visited Zonnestraal in 1928.  


Of course there are clear differences at every scale of analysis, particularly Paimio’s vertical emphasis and its smaller degree of transparency, both certainly motivated by considerations of the site or climate.  But the broader effort is consistent: to create architectural meaning from a need to provide sunlight, fresh air, and cleanliness for the patients’ recuperation.  The design solution at Paimio may be regarded as even more comprehensive than the Dutch example due to Aalto’s custom-designed furniture and fixtures. 

But again Paimio, like Zonnestraal, did not specifically seek to deliver solar heating or to save energy.

Also on the blog: Alvar Aalto and Solar Geometry

Selected Sources:
Richard Hobday, The Light Revolution: Health Architecture and the Sun, 2006.
Paul Overy, Light, Air and Openness: Modern Architecture Between the Wars, 2007.
Wessel de Jonge, “Zonnestraal: Restoration of a Transitory Architecture: Concept, Planning and Realisation in the Context of its Authenticity,” DOCOMOMO Proceedings, 2003.
Margaretha Ehrström, et. al., eds., “Nomination of Paimio Hospital for Inclusion in the World Heritage List,” 2005.