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BSMI revises standards to improve waterproof capability of buildings(Source: MOEA)

Water leaks are common in houses and they make up the bulk of real estate disputes in Taiwan. An effective waterproofing (water leak prevention) solution requires not only professional knowledge but also good waterproof materials. To improve the waterproof capability of buildings, the Bureau of Standards, Metrology and Inspection (BSMI) has revised two national standards: CNS 8644 'Liquid-applied compounds for waterproofing membrane coating of buildings' and CNS 10145 'Roofing sheets of synthetic polymer for waterproofing use.' Moisture and mildew prevention is important to people living in Taiwan, an island with humid and rainy climate. Water leak is also an issue because earthquakes often occur. Such problems not only affect living quality but also lead to disputes and accidents. The revised standards call for the use of high quality waterproof materials to ensure construction quality. According to CNS 8644, waterproofing membrane coating (such as polyurethane) can be divided into single and multiple component products by composition. They can also be categorized by areas of application: for roof use and exterior wall use. In CNS 10145, factory-made synthetic polymer waterproof sheets are separated into single ingredient composition and fiber enforced compounds. Both standards regulate waterproof products in terms of tensile strength, tear strength, fatigue durability and performance after aging. The standards also lists testing methods to ensure quality. CNS 8644 in particular regulates the maximum VOC content to improve air quality and ensure construction safety. Consumers and construction companies are urged to purchase suitable waterproof products to meet their needs. Please visit the CNS website at for more information. Agency in charge: Standards Division (1st Division) Contact person: Mr. Kuo-Lung Wu Telephone: (02)3343-5111