While the number of infected workers has gone up in many dormitories, several companies have bucked the trend, having taken pre-emptive measures to keep their workers safe from the virus.
Many cite early intervention as crucial in their efforts.
Local construction company, Woh Hup, which runs four dormitories with a total capacity of about 2,000, swung into action when news of the virus broke in January.
All its worksites stopped work for two days, and the workers were told to stay in their rooms while awaiting further instructions.
As of yesterday, Woh Hup had 12 confirmed cases among workers in its dorms.
The company had one of them, SK2 Dormitory, with a capacity of 372 beds, vacated and designated it a central isolation facility for workers on leave of absence, stay-home notice or medical leave. As of last Friday, there were 119 there.
Mr Neil Yong, a Woh Hup executive director and the chairman of the company's crisis management committee, said the dormitory was enhanced to provide properly partitioned rooms equipped with hot and cold water dispensers and personal electrical sockets to minimise interaction between residents.
The company also designed a detailed timetable to stagger activities and the use of facilities at its dorms.
Mr Yong said getting buy-in and compliance from all stakeholders was difficult at times, as some measures seemed like an overreaction.
To date, about 11,419 migrant workers who stay in dormitories have tested positive for Covid-19, primarily those living in purpose-built dormitories, such as S11 Dormitory @ Punggol, which currently has the biggest cluster with more than 2,200 cases.
It put the spotlight on living conditions in dormitories in Singapore.
Another local company, Unison Construction, has 224 foreign workers housed in a factory-converted dormitory in Tuas. So far, the four-storey dormitory in Tuas Basin Link has no Covid-19 cases.
About 13 to 15 workers share a room, with each getting at least 4.5 sq m of space. Workers from each room take turns to use the toilets and now also take their meals in their rooms, said the dorm manager who gave his name only as Mr Chang.
Mr Goh Boo Kui, contracts director of Unison Construction, which built the dormitory in the 5,000 sq m factory in Tuas in 2015, said: "Weeks before the lockdown, I already told my workers to avoid crowded places like Little India."
Straits Construction, which operates three dormitories housing about 1,200 workers, also has no cases so far. When news of the virus first spread, it implemented temperature screening before allowing entry into any of its projects.
And when signs of infections began to show up in dorms, the company converted vacant rooms in its dorms into isolation rooms.
Mr Clarence Chua, who runs landscaping firm Country Cousins, made the snap decision to pull his three workers out of Sungei Tengah Lodge when he heard about the cluster of three virus infections linked to the 25,000-bed dorm.
He moved them to a hostel on the night of April 6. Later, he moved them and seven other workers at Westlite Juniper to two rental apartments - one of which is a condominium unit in Bugis that he owns.
Sungei Tengah Lodge and Westlite Juniper have 874 and 24 cases, respectively.
While he is paying about 30 per cent more than what he would be paying for beds at the dorms, Mr Chua said he had no regrets.
He said: "In both cases, I got them out just in time. The least we could do was pluck them out quickly and not wait for fate to hit us."