Roofing in Oman

Oman's historic towns, forts and mountain villages are built of mud brick and stone with flat roofs carried on palm logs or imported timber. The undersides of these roofs, seen as ceilings, were often richly painted. Keeping earth roofs and wall tops intact through the rainy season has been the central conservation challenge at sites such as Bahla Fort.

Climate and hazards

Oman is hot and arid, with rain arriving in short, intense bursts. Earthen structures are vulnerable to rain and to poor site drainage: UNESCO notes that Bahla Fort was decaying rapidly after each rainy season before conservation began. Termites are a concern for roof timbers, which is why teak was favoured.

Roofing history

Medieval Bahla. The Banu Nebhan made Bahla their capital from the 12th to the end of the 15th century. Bahla Fort has walls and towers of unbaked brick on stone foundations.

Painted ceilings. Roofs of old Omani houses, mosques and castles were built from palm logs or from local or imported wood, including teak from India and East Africa. Ceiling logs were commonly painted dark brown or red with white patterns, flowers and animals, and sometimes carry the builder's name, the date of construction, poetry or Qur'anic verses. Jabreen Castle near Bahla, built in the late 17th century by Imam Bil'arab bin Sultan al-Yarubi, is known for its ceiling artwork.

Villages. Harat Al Seebani in Al Hamra, about 250 km (155 miles) from Muscat, was built about 400 years ago, according to local accounts, of clay bricks and mountain stone; by 2018 it had crumbling roofs and cracked walls.

Modern. New buildings are mostly reinforced concrete, as across the Gulf (see roofing-in-the-middle-east-and-gulf).

Traditional and vernacular roofs

• Flat earth roofs on timber: palm-log or teak beams with an earth covering, as across the Gulf (see chandal-roof).
• Palm-frond shelters: arish or barasti structures, part of the shared Gulf tradition (see barasti).
• Sarooj: a cement-like material made by firing discs of soaked mud on stacks of date-palm trunks and crushing the result. It has been used for centuries in Omani and UAE oasis communities, notably for building aflaj (irrigation channels); at Nakhal it is still made and shipped around the Gulf for restoration work. Some sarooj over 25 years old still behaved much like Portland cement.

Roofing today

Flat reinforced concrete roofs are standard in new construction.

Industry

Traditional sarooj production continues at Nakhal.

Notable roofs

• Bahla Fort (UNESCO): on the List of World Heritage in Danger from 1988 to 2004. Early-1990s repairs used unsuitable materials; from 1995 conservation used only earth-based materials, including new roofs, courtyard drainage and capping of ruined wall tops to stop collapse.
• Jabreen Castle: late 17th century, painted ceilings.
• Bait Al Safah, Al Hamra: a three-storey living museum of traditional life.

Local roofing terms

• sarooj - fired and crushed mud binder used in aflaj and restoration
• falaj (plural aflaj) - irrigation channel

Sources and gaps

Detailed climate data, national data on roofing materials, information on modern roofing materials, manufacturers and Omani building codes, and accounts of the use of mangrove poles in Omani roofs were not found in published sources.