Fujian Tulou Roofs

Fujian tulou are large, multi-storey earthen buildings in the mountains of south-western Fujian province, China, each designed to house an entire clan. Many were built by Hakka communities. Their thick earth walls are capped by continuous tiled roofs with very wide overhanging eaves. In 2008 UNESCO inscribed 46 of these buildings, spread over more than 120 km (75 miles), on the World Heritage List.

Form

Tulou are circular or square in plan and face inward around a central open courtyard, with usually only one entrance. Rooms line the outer wall on typically three to five floors, connected by timber galleries facing the courtyard. The UNESCO listing dates the buildings from the 13th or 15th to the 20th century, with the most elaborate examples from the 17th and 18th centuries.

The roof

The roof of a tulou follows the ring or square of rooms below it. It is a timber-framed, pitched roof covered in baked clay tiles. On round tulou the tiles are laid radially; because the outer circumference is longer than the inner, small extra tiles in a λ (lambda) shape are inserted to close the widening gaps. Unlike much formal Chinese architecture, the timber roof frame does not use dougong bracket sets.

Two features matter most:

• Wide eaves. The earth walls are vulnerable to rain. Overhangs of about 2 m (6.5 ft) throw water clear of the wall face and shade the upper storeys.

Climate and defence

Southern Fujian has hot, humid summers and heavy rain from monsoon and typhoon systems. The combination of thick earth walls and deep tiled overhangs keeps interiors relatively cool and dry. The buildings were also defensive: the outer wall is high and almost windowless at lower levels, and the roof sits above it as a single protective lid.

Conservation

Maintaining a tulou roof is labour-intensive. Broken or slipped tiles let water into the timber frame and onto the earth walls, which can then erode. Conservation work focuses on keeping the roof intact so the rest of the structure survives.