TREATMENT OF SALT ATTACK AND RISING DAMPNESS ON HERITAGE BUILDINGS IN MALAYSIA *
By
Associate Professor Dr. A Ghafar Ahmad &
Haris Fadzillah Abdul Rahman
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The research was fully financed by Universiti Sains Malaysia's Short-term Research Grant (2005-2007)
It is only recently that heritage buildings in Malaysia take its stage in the limelight. Heritage buildings are susceptible to deterioration due to several factors including climatic conditions, dampness and structural failures. A poor understanding of the extent and nature of building defects would result in carrying out inappropriate repair works during a conservation project, leading to disagreements and substantial cost implications amongst building owners, clients and building contractors. Amongst common building defects occurred in heritage buildings in Malaysia, salt attack and rising damp are considered the most challenging, particularly in building conservation. Thus, the research focuses on the efforts at solving the problems of rising damp and salt attack in heritage buildings in Malaysia. The research is important as part of the many efforts to conserve heritage buildings in the country. The problem of salt attack is closely related to rising damp. The moisture from the rising damp can either make the salts in the building material itself soluble or the ground water sometimes contains salt and finds it ways through the wall of the building. This moisture then evaporated on the surface or just below the surface of the wall leaving the salt residues behind. These formations will gradually contribute to the dilapidation of the buildings and also reduce the aesthetic value of the building.
Salt attack has been considered as one of the major building defects found in heritage buildings. Sodium chloride and calcium sulphate are commonly found in masonry walls even tough other forms of salts including calcium carbonates, chlorides, nitrates, magnesium, potassium and sodium may be the culprits. Sources of such salts may be from saline soils, groundwater (rising damp), sea-spray, air-borne (meteoric), cleaning compounds (detergent), urine, air pollutants and natural salts found in stone, brick clay or mortar sand. High salt concentrations in masonry walls may cause extensive fretting and crumbling of the lower parts of walls.
The research focuses entirely on salt attack and rising damp in heritage masonry buildings in Malaysia, mainly Penang. The main objective of this research is to find common treatment guidelines for salt desalination and rising damp that suit Malaysian context of architectural heritage and climatic conditions. Five buildings in Penang have been selected as case studies in the research. The research has showed that these buildings faced a few common building defects including salt attack and rising damp. Treatments have been applied to counter the problems during the conservation works. This report has nine chapters that discuss on various aspects of building conservation in Malaysia. It also includes guidelines on treatments of salt attack and rising damp.