Title: Earth construction in Najd of Saudi Arabia

Abstract

Najd’ is an Arabic word that means ‘highland’ and it is the central region of Saudi Arabia surrounded by Sharqiyah from east, Hejaz from west, Asir and Najran from south. Historically, earth is the major construction material of Najd for the last hundreds of years. Earth building in Arabian Peninsula traced back to thousands of years and archaeological evidence shows usage of sun dried mud brick in Najd from Abbasid era. Usage, types, construction techniques and quality of earth based material in the Najd region greatly varies. However, the durability and resilience of sun dried earth-based material in Najdi vernacular and historic buildings proved that it is worth researching and to use this material in urban construction. Aside from its durability and easy availability, the rich insulation quality of earth-based construction material made it historically appropriate and suitable to be used in Najd region. In summer, when in Najd region temperature goes up even as far as 54 0C, the earth walls keep the interior of rooms cool. On the other hand, in winter, during bitterly cold nights the earth wall makes the rooms containing desirable heat. However, during 1970-80s, a number earth structures in Najd collapsed due to heavy rain made the Saudi Arabian government banning the use of earth for building houses. It is the agenda of this paper that with innovative stabilisation of Najdi soil can potentially and safely be used in construction. The aim of this paper is to investigate on the typologies and suitability of locally available Najd soils appropriate for earth building. To achieve the aim, the paper critically reviews the up-to-date literatures and refine the information to establish whether locally available Najdi earth-based material is safe to use in construction.