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Building safety tips

【Layman's Guide on Rectifying Defective Drainage System at External Wall】

Misconnection, missing components, leakage and damage in drainage systems at external walls are common drainage problems.  Remember to arrange for drainage repairs promptly when you receive a statutory order from the Buildings Department (BD)!


Don’t know where to start?  Ah Build and Ah Ding are here to help!  Follow these steps to fix drainage problems at external walls for a safe and healthy living environment:


1.             Read the order carefully to understand the requirements

2.             Identify the category of minor works required to be completed and appoint a registered contractor of the respective category

u   Visit BD’s website for information on the costs for re-provision of anti-syphonage pipes at external walls for water closets

3.             Owner or a representative to notify BD after completion of the works

u   Owner to ask the registered contractor for a copy of the certificate of completion of works submitted to BD for record purposes

4.             BD to issue a letter acknowledging the compliance/discharge of the order

u   Owner to contact the registered contractor for follow-up actions if a rejection letter is received



Click the link below for more information about rectifying defective drainage system at external walls:






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