A restaurant set inside a greenhouse has realised a design flaw during the current heatwave.
The Brussels Sprouts outlet at the East Coast is one of many restaurants battling to keep business going as temperatures hit the mid-30s.
"The heat is uninviting to many potential customers," said manager Regemelec Angeles.
"We had to put up banners to block out the sunlight and install mobile cooling units to keep the place cool."
Temperatures in Singapore rose to 34.9 deg C on Thursday last week. In contrast, the highest temperature recorded in the month of April last year was 32.9 deg C, according to Meteorological Service Singapore. Other restaurants, such as those with alfresco dining areas, have also been under the weather.
"Business definitely dropped last week with the weather. The hot temperatures chased the customers away," said a spokesman for Shiraz Mazzeh in Orchard, which sells kebabs from an outdoor stall.
The hot spells have been punctuated with thunderstorms, something that outdoor businesses are also worried about.
"We saw a drop in business of about 5 to 10 per cent, but it's also because of the heavy rain lately," said assistant outlet manager Zerlie Reyes, 25, of the alfresco Coffee Club outlet next to Somerset 313.
"Business has been down 15 to 20 per cent this year," said Mr Dave Lim, manager of Cycle Max, a bicycle rental shop in East Coast Park. "Both the rain and the heat have contributed to this as people are not stepping out of their houses."
Sport has also been affected.
Mr Shimon Junior, admin manager of First Kick Academy, which runs children's football camps, said he is seeing more bookings for indoor than outdoor courts - even though indoor courts are pricier.
"Parents are concerned so we are considering holding our biannual tournament indoors this year for the first time," the 25-year-old added.
Construction companies such as Gammon are not taking any chances.
Senior project manager Zhang Lizhong said measures are in place to ensure the well-being of its workers. In the past two weeks, staff have been asked to spend longer resting in the shelter and to drink more water.
Singaporeans are taking their own individual measures.
"I try to avoid outdoor areas and shop indoors. It's very hot so I had to use the air-con more than usual," said project coordinator Derrick Wong, 41.
"I even choose to go night-swimming."
Student Karen Ho, 20, has resorted to more extreme measures. "I ask the hawker centre auntie for more ice. When she isn't looking, I will stuff the ice cubes down my shirt," she said.
A spokesman for the weatherman said the intermittent hot spells and thunderstorms are nothing out of the ordinary, as the inter-monsoon months of April to May are characterised by warm weather and occasional heavy thunderstorms.
Some places have even benefited from the conditions.
According to the Singapore Sports Council, the number of visitors to its swimming complexes increased by 10 per cent for the past two weeks compared to the first week of the month.