Jean Prouvé & Atelier d’architecture LWD
(Lagneau, Weill & Dimitrijevic).
Habitat tropical with standard timber frame.
This series model is derived from Jean Prouvé’s steel-frame prototype of 1958.
In 1964, the contract for producing six hundred and thirty-eight modules to house teachers and provide classrooms was awarded to Atelier LWD, following an international competition financed by the European Fund.
The resulting programme reflected a clever synthesis of traditional and modern techniques.
Designed on a module principle with 8,75 x 8,75 m as the centre-to-centre distance of bearing posts, dwellings were composed of either one or two modules and classroom buildings of from one to six modules.
As the fruit of collaboration between Jean Prouvé, consulting engineer, and Atelier d’architecture LWD (Lagneau, Weill & Dimitrijevic), this structure illustrates their research targeting a system of industrialized habitat for tropical countries, in particular Equatorial Africa with its hot and humid climate.
Unlike the Maisons Tropicales designed by Jean Prouvé in 1949-50, the process retained did not aim at 100% industrialization of construction, but at the series production of a few standard metal components to be used with local materials, and easy to assemble by local labour.
The prefabricated components were a roof tray and a façade panel in sheet aluminium, made in Cameroun by the Alucam plant at Edea, a subsidiary of the French firm Péchiney-Aluminium, and a folded sheet steel load-bearing post made in France.
The concrete mats, like the gable and façade walls (depending on the model, made of cement blocks or timber sheathing in forest regions) and the timber frame in red hardwood, were built by local labour.
The search for money-saving encouraged reliance on the natural resources of Cameroun and led the architects towards the massive use of timber for the series model, to replace the all-steel prototype designed by Jean Prouvé in 1958, which was too costly.
Most of these buildings have been demolished or spoilt by re-modelling, their fragile aluminium façade panels replaced by cement block walls.
The roof frame
The four bearing posts in folded sheet steel lacquered navy blue that stand at the four corners are shorter and thicker in section on the series model than on the prototype. Over them are laid and bolted the two robust side trusses in redwood, that carry the purlins to which the aluminium roof trays are fixed by hooks.
Purlins and trusses were assembled by screws and Japy bolts on the early examples built in the suburbs of the capital Yaoundé, but subsequently nails were used to cut costs.
The umbrella-parasol roof
An aluminium-tray roof, with a wide overhang surrounding the living space, constitutes an umbrella – parasol that protects against rain and sun.
Cooling is ensured by constant ventilation of the free space between the umbrella-parasol and the dropped ceiling, with cross ventilation facilitated by perforated wave panels and adjustable blades, known as “Nacos”.
The aluminium wave façade panels
This construction system offers maximum flexibility of use. Several façade layouts are possible, which even on the same module may be identical or different.
The example shown on our website has two identical façade modules; they are fitted with two mobile panels that serve as doors, sliding in a hardwood groove (top) and guided by a tube metal runner (bottom), and are framed by two fixed panels.
On the prototype, however, certain modules were fitted with a single sliding panel framed by two fixed panels, with either one or two wall planes.
A panel set is composed of two side uprights in timber lacquered sky blue, routed with grooves to hold the ends of seven large horizontal waves (eight waves on the prototype). The waves are made of ribbed sheet aluminium; they were riveted together (as on the prototype) on the first examples built, and later mounted interlocking one on top of the other.
Specially designed by Jean Prouvé, the waves are perforated on their lower edge to let in daylight and ensure ventilation.
Two vertical panels lacquered sky blue, using the “Nacos” system with timber laths and moveable glass blades, frame each of the two modules.
Bibliography
– ATEA, « Système d’habitat en zone tropicale humide », c. 1964.
– Joseph Abram « Le rêve du réel, de la maison du Sahara aux écoles du Cameroun » Faces, 1995.
– Joseph Abram, « L’architecture moderne en France » Ed. Picard, 1999, pp. 264-265.
– « Jean Prouvé, la poétique de l’objet technique », Ed. Vitra, Weil am Rhein – 2004 pp. 222-223.
– Peter Suzer, Jean Prouvé Œuvre complète, volume 4, 2008, Ed. Birkhauser, pp. 180-181, 300.
– Eric Touchaleaume, Jean Prouvé / Atelier LWD, les constructions SOFRA, published in 2015.