ABU DHABI // A local developer that had a number of windows shatter in one of its high-rise buildings, says the windows’ installation “outperforms construction norms”.
Residents had voiced concerns about safety after inner panes in two tempered-glass windows spontaneously shattered last week. Aldar said it was replacing the glass and was further investigating the cause of the breakage.
“Following the inspection, the engineers confirmed that the likelihood of spontaneous glass breakage in Gate Towers is very low,” Aldar said.
“After 15 months since the tower was completed, and more than two years from the glass installation, there have been only three incidences of windows cracking – this outperforms construction norms.”
Residents in three Gate Towers apartments and another in the Arc, also part of the structure, said they had window damage.
Spontaneous glass breakage can occur in tempered glass, the type used in Gate Towers. The glass is built to shatter in small pieces rather than large shards.
Gate Towers’ facade has more than 44,000 double-glazed units, a total of 88,000 glass lites, with eight-millimetre and 10mm glass lites separated by 16mm of air.
“It’s not uncommon for tempered glass to break spontaneously and there are a number of reasons why it happens,” said Russell Winser, an associate director at BuroHappold Engineering and an expert in building facades. “To try to minimise failures, there are a number of additional quality control processes that can be carried out.”
Factors that contribute to glass breakage include damage during installation or wind and temperature changes.
Aldar said the glass underwent heat-soak testing, which significantly reduces the likelihood of breakage caused by nickel sulphide inclusion defects that can occur during manufacturing.
Mr Winser said that because spontaneous glass breakage was a risk with tempered glass, it was usually recommended that its use be minimised. However, it can be the most appropriate to use depending on design and other factors.
“If it’s a very tall building with a high tonnage of tempered glass, the likelihood of failure is higher than a smaller building with less tempered glass,” he said.
During design development, it should be ensured that the glass suited the requirements of the building.
“I think the most important thing is correct specification, correct processing and careful handling during installation,” Mr Winser said.
Aldar said that the residents whose windows had broken last week would have them replaced within a week.
“The safety of our residents and employees is of paramount importance and both Aldar and Khidmah take this matter very seriously,” the company said, referring to the facility management company for Gate Towers.
Residents whose windows had broken previously, said having them replaced had taken much longer.
Shawwal Shahid, 29, said he came home to his apartment in the Arc in August to find that the window pane had broken. Initially he was afraid it would fall down and posed a threat to other people, since he did not know there were two layers.
“It took 106 days for them to actually come and fix it,” said Mr Shahid, who has a one-year-old daughter.
lcarroll@thenational.ae