Falling concrete cases spur call by engineers

Property owners should conduct regular checks of residential buildings and seek assistance from qualified inspectors to carry out maintenance works at an early stage if they find any problems, the Hong Kong Institution of Engineers said, pointing out that some 5,200 buildings in the city posed safety risks.

The call was made yesterday after a series of concrete falling incidents took place recently, including the latest incident on Tuesday at an optical shop in Sino Centre in Mong Kok, that saw a 58-year-old man injured in the head.

The condition of about 5,200 buildings, making up 20 percent of buildings aged above 30 years old, are "poor" or "dilapidated" as of last year, the institution said.

It expects more than 20,000 buildings - almost half of buildings aged over 30 years old in the city - will be at risk by 2046.

"Buildings will inevitably develop different problems as they grow older like humans. If we wait until problems arise before tackling them, the time and money required will increase correspondingly," said president Barry Lee Chi-hong.

Concrete spalling is generally caused by prolonged exposure to moisture, aging of concrete, minor cracks in concrete due to hot weather and temperature difference, or damage to waterproofing coatings, it said.

Unauthorized building works may also pose risks of falling concrete as they increase the load on a building.

"Although concrete spalling will not immediately endanger the building structure, it had already triggered an alarm, indicating that there was a problem with the condition of the building, and that the problem would be aggravated if it was not remedied immediately," Lee said.

The institution suggested people seek inspections by registered inspectors rather than carrying out repairs by themselves if they find any obvious damage, such as water stains or rust on the surface, falling of canopies, tiles, paint or wallpaper, or cracks or bulges on the wall.

"If structural problems or concrete spalling are involved, people should contact professional structural engineers as soon as possible to assess whether there is any immediate danger to the structure of the building and conduct repairs accordingly."

Lee also suggested authorities strengthen public education to get an in-depth understanding of building inspection procedures.

The institution has also updated a guide on building safety and maintenance to give owners a better understanding of maintenance.