Real Hong Kong News (based on multiple sources)
2nd December, 2015
Concrete Blocks Flew Out from Structural Wall at Tin Shing Court, Tin Shui Wai
Around 7pm on 30 November, when Ms Chow and her son were having dinner at home in Tin Shing Court, Tin Shui Wai, the structural wall of the flat which separates the living room and kitchen suddenly gave a loud crake and concretes flew towards the legs of Ms Chow and her son. The largest piece of concrete measured in over 50cm diameter.
After initial inspection, two pieces of concrete approximately 1 x 1.5ft and 0.5 x 1.5ft in size came off from the structural wall at Ms Chow’s unit, which revealed severely rusted steel bars inside the wall.
Ms Chow said that a 1ft long crack was spotted on the wall since over a year ago, which goes from starts from the floor level towards the ceiling, and the wall where the crack begins is puffed up too. She was planning to renovate the unit in 2 to 3 years’ time after spotting the crack.
On 1 December, after professional inspection was conducted, the structural wall of Ms Chow’s flat was found to have “hollow spots”. The neighbouring units at the same building are also found to have these hollow spots on their structural walls. Housing Authority’s structural engineer said that the structural walls will need to be rebuilt.
Lai Tat-ming, an independent Clerk of Works, also inspected Ms Chow’s flat and found that the areas where concrete fell out contain more sand and rock than cement, which is the main reason for the steel bar to get rusted and eventually popped out from inside the concrete. His radar scanner reading shows multiple hollow spots on the structural wall and the thickness of the concrete is only 10mm, which does not meet the requirement stipulated in the Building Ordinance (Ch 123B, R62) – for slabs and walls in enclosed buildings have to be at least 15mm in thickness to ensure steel bars are protected from moisture in the air).
The construction of Tin Shing Court, a precast estate, was completed in 1999. Mr Lai also found that there are holes in the precast walls (the structural wall of Ms Chow’s unit) have not been filled with concrete.
Although Housing Authority said that the problem at Ms Chow’s unit is an isolated case, it is confirmed that at least four units in Tin Shing Court have similar problems: cracks appearing on walls and concrete blocks coming off the walls. One of the cases is a unit with a 4ft long crack on the wall.
Tin Shing Court had been reported to have problems with its structure soon after the estate was completed. In 2000, it was reported that Tin Shing Court experienced substantial uneven settlement which required emergency foundation strengthening work, and problems with the precast components used for building the estate. Tin Shui Wai New Town, where Tin Shing Court is located, have already seen some serious construction scandals, including foundation piles found to be shortened by up to seven meters than the standard requirement (1999).
Tin Shui Wai New Town Public Housing
|Tin Shing Court –
Phase I (Block B, C & D)
|Hong Kong Housing Authority||Block B: Hsin Chong Construction Group Ltd
Block C & D: China State Construction (HK)
|Tin Shing Court –
Phase II (Block E, F, H, J, K, L, M, N & O)
|Hong Kong Housing Authority (Block E & F)
Wong & Ouyang (HK) Ltd (Block H, J, K, L, M, N & O)
|Block E & F: China State Construction (HK)
Block H, J, K & L: Nishimatsu Sintec Construction Ltd
Block M, N & O: Hsin Chong Construction Group Ltd
|Tin Shing Court – Phase III (Block A, G, P, Q & R)||Simon Kwan & Associates Ltd (Block A, Q & R)
Hong Kong Housing Authority (Block G)
Wong & Ouyang (HK) Ltd (Block P)
|Block A, G, Q & R: Hsin Chong Construction Group Ltd
(Sources: Apple Daily, Sing Tao Daily, Ming Pao, Wikipedia)