Roofing in South Korea

South Korea's traditional roofs belong to the hanok, the Korean house, which was roofed either with fired clay tiles (giwa) or with rice-straw thatch (choga). In the space of a few decades in the later 20th century the countryside was re-roofed with cement-based slate and tile, and the cities were rebuilt as high-rise apartment districts with flat concrete roofs. The legacy of asbestos-cement slate is now a public-health programme.

Climate and hazards

The peninsula has hot, humid summers with a monsoon rainy season and occasional typhoons, and cold, dry winters. Traditional roofs were tuned to this: the depth of the curved eaves (cheoma) blocks the high summer sun but lets low winter sun into the rooms, and thatch was renewed before the summer monsoon. On windy Jeju Island, thatched houses (chojip) were built low to withstand strong winds.

Roofing history

Prehistory. Pit dwellings of the Mumun period had thatched roofs over wattle-and-daub walls; Chinese records describe early Korean houses with a grass-and-clay superstructure on a timber frame. Choga houses evolved from these Neolithic and Bronze Age dwellings, and rice-straw thatch is linked to the spread of rice cultivation by the Three Kingdoms period.

Tile. Fired roof tiles derive from the Chinese tile tradition that developed under the Western Zhou and later spread to Korea. Tiles were used on official buildings in the Chinese commanderies on the peninsula after 108 BCE, and became established with Buddhism in the 4th century. Goguryeo palaces in Pyongyang used patterned tiles with ornate bracket systems; Baekje produced lotus-pattern roof-end tiles and in 588 sent tile makers to Japan; Silla tiles survive in large numbers from Gyeongju. Under Goryeo, celadon-glazed tiles were used on some elite buildings. Large halls carried their roofs on bracket sets, from simple Goguryeo brackets to the multi-bracket systems that developed from mid-Goryeo to early Joseon, and ridge ends carried owl-tail tiles called chimi.

Joseon to modern. Tiled houses (giwa-jip) belonged mainly to the upper and middle classes, while choga was the dwelling of working people from prehistory to the mid-20th century. Choga began to decline in the 1960s with rapid industrialisation. The New Village Movement (Saemaul Undong), launched on 22 April 1970, spread orange-tiled houses through the countryside in place of thatched choga, and by the 1980s thatch had largely given way to cement and slate roofs. Many of these slates were asbestos-cement, containing about 10-15 per cent asbestos, and were widely used for roofs and ceilings from the 1970s.

Traditional and vernacular roofs

• Giwa-jip - tiled hanok with heavy, gently curved roofs that turn up at the corners; roof-end tiles carry stamped motifs.
• Choga-jip - rice-straw thatch, sometimes wheat straw or grass, renewed every one to three years as a community task.
• Roof forms - the hip-and-gable paljak roof (paljakjibung) was the most common form for important Joseon buildings.
• Jeju chojip - low thatched houses behind dry-stone walls (chukdam) that let strong winds pass through.

Roofing today

Apartment and commercial buildings, which house most of the population, have flat reinforced-concrete roofs waterproofed with membranes or liquid coatings, often with rooftop plant and increasingly solar panels and green roofs. Detached houses use asphalt shingles, coated steel sheet, or clay and concrete tiles. Since 2011 local governments have run subsidised slate removal programmes; Gwangju alone had removed or supported removal of 4,462 slate buildings by 2025, with grants for removal and, for low-income households, re-roofing.

Codes, standards and regulation

Building work is governed by the Building Act and its Enforcement Decree. The decree treats work on roof trusses as a test of "alteration" and "substantial repair", with a specific exception for the rafters of hanok, reflecting government support for traditional construction.

Notable roofs

• Bukchon Hanok Village, Seoul - designated a folk landscape area in 1976 and a hanok conservation zone in 1983.
• Jeonju Hanok Village - more than 800 tiled hanok.
• Hahoe Folk Village (UNESCO, with Yangdong) - tiled and thatched houses, some over 600 years old.
• Nakan Eupseong, Suncheon - about 300 thatched houses re-thatched each year after the rice harvest.

Local roofing terms

• jibung (지붕) - roof
• giwa (기와) - roof tile
• choga (초가) - thatched house, "grass house"
• cheoma (처마) - eaves
• chimi (치미) - owl-tail ridge-end tile
• paljakjibung (팔작지붕) - hip-and-gable roof

Sources and gaps

National statistics on roof materials, the number of asbestos slate buildings remaining and industry data: published information is limited.