Qadad

Qadad (Qadâd, Kʉðað) is a waterproof plaster surface, made of a lime plaster treated with slaked lime and oils and fats. The technique is well over a millennium old and can be used as a roof covering.

Due to the slowness of some of the chemical reactions, qadad mortar can take over a hundred days to prepare, from quarrying of raw materials to the beginning of application to the building. It can also take over a year to set fully.

In 2004, a documentary film Qudad, Re-inventing a Tradition was made by the filmmaker Caterina Borelli (preview). It documents the restoration of the Amiriya Complex, which was awarded the Aga Khan Award for Architecture in 2007.

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