PRESERVATION \ CONSERVATION \ Architecture \ 735c
1: S. Bonetti, November 2002

Conservation of the palace walls

Clicl here to see video.

     In the last two years an in depth study was undertaken that had as its aim to monitor the condition of the mud brick palace walls. This kind of walls, typical in all of the Near East, and still used today, is subject to serious damage by wind and rain and by the high difference in humidity between summer and winter. If left exposed to the elements, they crumble and disintegrate within a few years, as can be seen in many archaeological sites. Briefly, the solutions used so far in sites similar to Mozan are either to cover the whole site with a large roof, or to cover the walls themeselves with a natural or sinthetic mortar. Both these devices are not entirely satisfactory, the first because the walls are still somewhat exposed and do not build a discernable whole, the second because, while showing clearly the form of the structure, the mortar completely and permanently hides the original material.

     The protection system introduced at Mozan by G. Buccellati consists in covering the walls with a thick, waterproof fabric that the locals use for their tents, applied over a metal “cage” that follows the profile of all of the walls (V13d8088). A test was carried out in a particularly well preserved room, the kitchen of the palace (V13d9453); it was also a way to check on the visual effect. As expected this turned out to be very interesting, because the reconstructed profile of the walls was also a visual help for the understanding of the palace structure: it looked like a virtual reconstruction of the building, except that it is real. In 1999 a massive operation was started to cover the whole exposed palace with the same method (V13d8417). The tents were tailored on the metal structure and sewn in the excavation house.

     In 2001 we decided to systematically check the conditions of the walls in order to determine how well the covering system works and how it can be improved. Basically we had to develop a better closing system between the fabric and the metal structure, since the wind turned out to be one of the worst sources of damage, and on making the walls themselves more accessible: for example, at the beginning the fabric was sewn in a way that all corners were closed and there were few scattered apertures in the fabric that could be opened as kind of window and rolled up showing thus the wall surface (V13d8561). If one wanted to see the whole face of a wall exposed, the whole tent cover had to be removed from above, and this would have requested at least 2 or 3 people and quite a bit of time. Several changes have been planned to improve the handling of the covering system in close cooperation between the archaeologist and the conservator: for instance, all corners were made openable, allowing the lifting of a whole panel with a system of rods and hooks in a matter of a few minutes, making the wall face entirely visible (V14d7712).

     The conservator's task was that of supervising the changes in the covering technique, and that of monitoring the situation by taking digital photos of every wall and writing a series of notes in the form of a diary. During the last 2 years, a check was made from 3 to 5 times per season, each time with a particular objective in mind, for instance, checking the state of the tops of the walls, or the conditions of the fabric. A monitoring of the temperature and humidity throughout the year has been carried out with the help of a very valuable assistant who lives in the village, Ibrahim Khellu, who provided a chart of the values, taken twice a day every day. The result of this survey with the detailed information will be published in due time. We can certainly anticipate that the method seems to work well over longer periods of time, but that it involves a certain degree of maintenance since the fabric is obviously affected by ageing.

     In 2002 we have replaced some of the old fabric with a new type, suggested by the tent maker; the new fabric has been tested and is perfectly waterproof. The survey of the walls and of the covering method will continue and hopefully the result will be optimized so that with a known, standard level of maintenance we will be able to preserve the palace walls indefinitely.

     It must be kept in mind that one of the highlights of this system is its complete and relatively fast reversibility: to take the aerial photographs of the site, for instance, the whole building can be uncovered, and the metal structure removed in two days.

Back to top