Structural Stamina

Due to the harsh climate of the region, Omani buildings require a very specific construction process that can withstand and protect against the environmental factors. This includes design and layout of the building as well as the materials used to construct it.

Siting was a very important factor to take into account. The buildings usually had a long east-west axis that minimized the eastern and western facades from receiving direct sunlight and leaving larger northern and southern facades. This is very evident in the layout of the Nakhl Fort. From the complex overall layout to the shaping of the smaller inner buildings this method ensured that the majority of the structure would not receive direct sunlight which would have drastically raised the temperatures inside the fortification.

In the layout of the fort, the bulk of the buildings are located on the eastern side of the compound, while the mainly uninhabited spaces are on the western side where the impact of the sun is significantly more intense. The sleeping quarters and other night-time places are oriented to the cooler night air. In terms of design, the windows and openings that face the sun are usually smaller which helps to keep extra heat out, as well as dust. In rooms where windows are necessary, there are larger windows along the bottom of the walls, where cool air comes in and smaller windows located along the top of the rooms, out from which the hot air escapes. This circulation of air helps to maintain a cooler room temperature.

A view of the Majlis (Source)

All Omani Forts share similar room characteristics, and Nakhl is no exception. In the more important rooms, such as the local governors Majlis (council chamber) the ceilings are elaborately painted and carved. The women's rooms are located in the most private area of the fort, typical of the era it was built, and sport richer decorations than the rest of the Fort's rooms, particularly wood or lattice screens across the window. The sitting rooms have excessively thick walls, to keep the sunlight and consequent heat from travelling through the walls until nighttime, where the mud brick construction acts as a thermal mass and protects the inhabitants from the cold. In the lower levels of the fort there is a Falaj (water supply channel), as well as wells, hot springs, and cisterns for water storage. Due to the consequent expansions and restorations, the Forts lower levels consist of labyrinthine passages and hallways, as well as dungeons too low to stand up and too narrow to sit down in.

A view of one of the many inner tunnels (Source)

The fort is constructed mostly of mud brick. The bricks are created from mixing sand and clay from the earth with water, as well as adding chopped straw or palm leaves. The mixture is then rammed into a brick form. The straw and palm helps the bricks dry evenly and prevents cracking. After the bricks are laid, they are coated on the exterior with a similar mud called sarouj that helps seal and protect the building as well as making it aesthetically pleasing. The sarouj is a rural ingredient of handmade mortar and plaster. It consists of soil from date palm groves, which is mixed with water and dried in the sun. It is then baked in a traditional oven, and then mixed with other local ingredients to give it a characteristic light tan colour, and finally baked one last time in the sun. Date Palm trunks are used in the foundations, as ceiling supports (joists and rafters) and in some of the larger walls to help strengthen the structure.

Defensive cannon on top of the fort (Source)

Nakhl was designed mainly as a defensive fort, and similar to forts built after 1500 in the area, it is designed for cannon fire. The tower turrets are elevated higher then pre-cannon constructions, to offer a better view and farther range for the cannons. Consequently, all the walls of the fort are thicker, either to withstand the shock from their own cannons firing, or constant enemy bombardment. The walls of the fort are pockmarked with tiny, downward slanting slits, which were designed for firing muskets at invaders without being exposed to enemy fire. All the doors and gates have a low, 1 meter high doorway. This would force enemy invaders to bottleneck and enter one at a time, with their backs bent in a vulnerable position. As well, in case enemy forces managed to penetrate all the other defenses, their were slots located above doorways and openings in which boiling hot liquids could be dumped onto enemy bodies.

-Dave Holborn and Andrew Winters

Information Citations:

Lawrence, A.W. Trade Castles & Forts of West Africa. Stanford: Stanford University Press, 1964.

Oliver, Paul. Encyclopedia of Vernacular Architecture of the World.Cambridge: Cambridge University Press, 1997.

Toy, Sidney. A History of Fortification. London, Heinemann Educational Books, 1966.

Image Sources:

Kijal. "Path of Darkness" (image). Available from: flickr.
http://www.flickr.com/photos/kijal/131160960/in/photostream/
(accessed January 10 2010).

Kijal. "Protection" (image). Available from: flickr.
http://www.flickr.com/photos/kijal/130557871/in/photostream/
(accessed January 10 2010).

Kijal. "Welcome to the Majlis Room" (image). Available from: flickr.
http://www.flickr.com/photos/kijal/131160955/in/photostream/
(accessed January 10 2010).