SINGAPORE - She was in the living room taking care of her grandson when she heard thunder crashing in the distance at about 10.10am.
What followed was an unusual sound of metal cracking.
Madam Heng, 70, who declined to give her full name, said it was not until her son came home on Monday evening (April 19) that she found out that a 12m-tall steel structure had collapsed near a Build-To-Order flat construction site across the road from her home in Bukit Batok.
No one was injured in the incident, the Ministry of Manpower (MOM) told The Straits Times.
MOM said the incident occurred on a piece of land next to a proposed HDB public housing development bordered by Tengah Garden Avenue, Plantation Crescent and Tengah Boulevard.
The 12m-tall steel structure was being erected when part of it collapsed onto temporary worker's quarters, which were unoccupied.
No one was staying there yet as the accommodation is still under construction.
In response to ST's queries, HDB said the incident happened on a plot of land next to the Tengah BTO site. There is a Temporary Occupation Licence for the land, which is being used for the worker's quarters, storage, and pre-fabrication works supporting the BTO development.
HDB has stopped all work at the site, cordoned off all affected areas and the occupier of the site will be developing a recovery plan, MOM said. It is working with HDB to establish the cause of the incident.
The occupier of the site is HPC Builders and the sub-contractor for the steel structure is Epoch Metal.
The Singapore Civil Defence Force said it had received a call for help at the construction site near the junction of Tengah Drive and Bukit Batok Road at about 2.05pm, but no assistance was required in the end.
It is not clear why the call was made only hours after the incident.
Madam Heng's son, Mr Tan, who works in the construction sector, said it was unlikely that the heavy rain and bad weather had caused the collapse.
The 37-year-old, who also declined to give his full name, said he had paid close attention to the construction work at the site. The steel structure, along with another one like it, were put up only in the past week.
He added: "It looks like it is a failure of the steel members. It is very lucky that there were no workers residing in the temporary living quarters at that moment."
Mr Arjun Nair, a safety officer with experience in construction, said a number of factors, including the heavy rain, could have played a part. "It might be a design issue," he said. "The inclement weather might also have been critical."
But Mr Nair said it was also lucky that the collapse happened during the heavy downpour. "Usually when it is raining, most workers at construction sites stop work and take shelter. If it was not raining, there's a high chance some workers might have been injured."
