Roofing in Papua New Guinea

Papua New Guinea has one of the world's most varied traditions of vernacular building, from stilt houses in coastal swamps to Highland houses and the towering ceremonial houses of the Sepik. Most traditional roofs are steep thatch of palm leaf, pandanus or grass on timber and bamboo frames lashed with vine or cane. Corrugated metal is now the most common roof on main dwellings, but thatch remains widespread.

Climate and hazards

The climate is tropical and wet, so steep roof pitches that shed heavy rain quickly are a constant feature. The country is seismically active; traditional joinery using mortise and tenon or vine lashing produces frames that can flex in earthquakes and strong winds. Coastal and swamp settlements are raised on posts against flooding.

Roofing history

Reliable dates for early roofing are scarce. What is documented comes largely from ethnography of the 20th century. In the Maprik area of East Sepik, anthropologists Anthony Forge and Donald Tuzin described ceremonial houses built on a triangular plan with no walls and no floor: heavy wall plates slope to the rear on posts sunk about 3 m (10 ft) into the ground, a massive ridge pole is raised at dawn on temporary supports, and a diaphragm of slender bamboo rafters then takes the load so that the ridge sags slightly, giving the house its hunched profile. Anthropologist Brigitta Hauser-Schäublin records that Abelam ceremonial houses reached heights of up to 30 m (about 100 ft) and were built by communal labour without nails, bound with vines and liana ropes.

Haus tambaran have become less common as Christian fundamentalism has spread, and in 1984 the national Parliament House in Port Moresby, opened by Prince Charles on 8 August 1984, adopted the haus tambaran form for its entrance facade, a design also shown on the 50 kina note.

Traditional and vernacular roofs

• Haus tambaran (spirit house): Sepik men's ceremonial house with a tall, painted front gable and a ridge that slopes down toward the back, the roof often reaching the ground. The Abelam form (korambo) can be about 25 m (82 ft) tall and is thatched with sago palm fronds.
• Stilt houses in coastal and swamp areas, with walls and roofs typically thatched with palm leaves or grass.
• Highland houses, round or oval and partly sunk into the ground for insulation around a central hearth, and large, decorated Mendi men's houses.
• Marita: pandanus-leaf thatch, sewn into roofing panels, described as the most common roofing in the lowlands.

Roofing today

In a World Bank high-frequency phone survey of 2020-21, 59.5% of responding households said the main roof of their dwelling was metal and 36% said thatch or palm leaf; wood, bamboo and other materials made up the rest. These are case counts from the survey sample rather than weighted national estimates. Metal roofs dominate towns, while thatch remains common in rural villages, where materials can be gathered and replaced locally.

Codes, standards and regulation

PNG has no unified national building code. Building is regulated under the Building Act 1971 and building regulations based on Australian standards.

Notable roofs

• National Parliament House, Port Moresby (1984), with a haus tambaran-style gable.
• Abelam ceremonial house gable in the Naturhistorisches Museum Nürnberg, taken down around 1975 and re-erected in Germany; an Abelam cult house replica is also displayed at the Humboldt Forum in Berlin.
• Haus tambaran from Apangai, Maprik District (1984), in the National Museum of Ethnology, Leiden.

Local roofing terms

• Haus tambaran (Tok Pisin): spirit or ceremonial house.
• Marita (Tok Pisin): pandanus-leaf roofing; wokim marita, to make roofing; soim marita, to sew roofing.
• Kunai: grass used for roof thatch.

Sources and gaps

No well-documented date for the arrival of corrugated iron in what is now Papua New Guinea was found in published sources.

Modern manufacturing and on cyclone performance: published information is limited.