Forget the new interactive exhibitions, the Vimto mojitos and the falcon displays – the issue that is certain to be on most people’s lips during this year’s Qasr Al Hosn Festival is the changing face of one of Abu Dhabi’s most important monuments.
Thanks to a conservation process that has stripped Qasr Al Hosn of the white render that has defined it since the early 1980s, the ‘White Fort’ has been replaced by something rougher, greyer and ultimately more complex.
“The festival always shines a spotlight of where we are with the works but this hasn’t been done because of the festival,” says Mark Kyffin, Abu Dhabi Tourism and Culture Authority’s head of architecture.
“You’ve just caught us at the end of one phase of work and the beginning of another. We now almost have an X-ray view through the building that’s providing us with a window into the construction techniques and building technologies of the past.
“By exposing it in the way we have we can understand where the building needs to be repaired and how the different periods of construction have become merged and interlaced with one another in a single elevation.”
The aim, Mr Kyffin says, is to return Qasr Al Hosn to something approximating its original state, with traditional materials giving the fort a more natural and historically accurate white.
That process started with a long period of archaeological and architectural investigation and is now about to enter its final phase. But before building could begin the fort’s outer layers had to be removed for preparation and the building’s health.
“In the 1980s, the building was covered with two coats of render on top of the original coral stone – a layer of grey cementitious render and a layer of white gypsum render on top of that,” Mr Kyffin says.
“That made it very difficult for heat to escape and resulted in the formation of a layer of interstitial condensation that caused the render to decay.”
That decay was the result of a material mismatch between the non-porous renders that were used when Qasr Al Hosn was restored and rebuilt in the early 1980s, and the original materials from the 1940s and earlier that allowed the fort’s walls to expand and contract with changes in temperature.
The beauty of Qasr Al Hosn’s original render – a form of beach plaster, juss bahar, made from burnt and crushed coral, sand and sea shells – lay in the fact that it was made from the same materials as the fort’s underlying structure.
This allowed the building’s walls and cladding to behave in unison and gave them insulating properties, absorbing the heat during the day and releasing it at night in a manner that helped to protect Qasr Al Hosn’s residents from the elements.
“We want to allow the walls to breathe again, to appreciate the manner in which the original building was constructed using coral and sea stones and to see the painstaking efforts the masons made at the time,” Mr Kyffin says.
“We want the building to be legible, so that the public can read each chapter of its evolution, so that its walls talk to the people of this place but also to allows others to understand how complex and how beautiful its fabric is.”
nleech@thenational.ae