The construction
 of Clan homes in Fujian

Jens Aaberg-Jřrgensen

ChinaDwelling.dk

Zhenchenglou, Hongkeng

Originally published in Danish in ARKITEKTEN  no. 28, November 2000, pp. 2-9. 
Text and illustrations have been updated for the web edition. (JAA-J, 2003-04).


Click here to go the survey of the circular tulou 
Zhenchenglou
in Hongkeng village


The foundation
 is of large rounded stones from the local river, filled out with smaller stone. In this frost-free region the foundation's function is purely to support the weight of the building.
The base 
normally 60-90 centimetres high, is also of large stones, the largest of which are placed at the core of the wall. Both sides are plastered with clay.
The outer wall
The terre pisé technique, labour-intensive but cheap, is widespread in China. The erection of such high walls requires fine sedimentary mud from the rice fields, the very same mud that makes for a rich and productive agriculture.

(Olivier Laude, Unique Habitats, p. 163-173 in ‘Village Landscapes’, ed. by Ronald Knapp, Hawaii, 1992).

(According to Ronald G. Knapp: China's Old Dwelling, Honolulu 2000, p. 260 and 266, the use of the term earthen dwellings and tulou is a misnomer. Some tulou were actually constructed completely of cut granite or had substantial walls of fired brick. Most large-scale tulou seen today were built of a composite material known as sanhetu rather than just earth. In calling these structures "tulou", however, one must be careful to qualify the term as a broadly descriptive label for a building type rather than as a narrow term defining a specific building material).

Zhenchenglou, Hongkeng

Rushenglou, Hongkeng

The stamping is carried out with the use of a wooden frame, 2 metres long, which is used as a mould. This is filled with suitable type of mud, or a mixture of earth, sand and lime called sanhetu, then pounded with a stone or a thick staff.

Maximum strength is obtained if each layer is allowed to dry slowly and cojpletely before the next layer is applied. The wall is further strengthened if allowed to dry gradually, before the next layer is built on top.The wall is reinforced with split bamboo canes or, in the case of corners, L-shaped cedar branches. The outer wall leans inward to counteract the outward forces and in the case of the circular tulou aids the support of the cantilevered wooden construction.
The pressure also increases the wall's resistance to erosion. (Ole Vanggaard, personal communication, 1999).


Stamping the outer wall



The mould


In the past all the tulou in the locality were whitewashed. (John Lagerwey, personal communication, 1997). This protected the facade against rain, and also reflected solar heat, helping to reduce overheating, a useful effect in the south Chinese summer. I saw very few completely whitewashed buildings. Whitewash was applied only to the window frames.

Whitewashed tulou

The wooden
structure
 
includes all decks and columns and is built in parallel with the completion of each terre pisé floor level, with the outer wall and columns bearing the beams. Almost everything but the outer wall and roof cladding is constructed of wood, normally pine. The wooden flooring is fastened with wooden pegs, singed in hot sand to increase durability.
The fire wall 
stabilises the tulou and in some cases is used to subdivide the building.

Outhanging eaves

Wooden construction,
fire wall
 

The roof construction

The large tulou require about a year per floor to build. After three or four years the top floor is reached and the roof construction can begin. It takes a year to complete with a slightly downward-curving cladding of grey locally fired tile.
The remaining interior construction is of wood (partitioning walls, stairs, flooring, doors, windows etc.) and takes a further year to build.

Overhanging eaves

Stairs

Roof
It was very labour intensive to build a tulou with its enormous size and corresponding requirement of clay and timber. The construction was carried out side by side with the peasants' other activities. Skilled workers were brought in only for the more complex carpentry and masonry. The tulou is the largest traditional rural housing type in China, possibly in the entire world. The rooms, while relatively small, are far more numerous than in any other type of building.