How United Tec built the world’s tallest modular building project

27 Sep 2022


As the last building module was placed on top of the Avenue South Residence (ASR) project at the start of this year, Mr Allan Tan beamed with pride.

“Mission accomplished,” exclaimed the Managing Director of United Tec, the main contractor of the 56-storey twin towers, which stand at 192 metres tall. 

Situated along Silat Avenue at Bukit Merah, near downtown Singapore, the 1,074-unit condominium now holds the world record for the tallest residential tower built using prefabricated prefinished volumetric construction (PPVC). The construction method sees 3D modules completed off-site before being assembled like Lego blocks on-site.

“When we completed the project and realised it worked, it was such a huge relief,” he shared of the challenging project that required the modules to be lifted at unprecedented heights. 

“We strongly believe the future is innovation,” said Mr Tan, who chalked up plenty of know-how in PPVC at his previous company when completing the then tallest PPVC building, the 40-storey Clement Canopy.

PPVC and other innovations

Mr Tan, who founded United Tec in 2018, and now holds the new record with ASR, credits his team for the success – from workers involved in factory fabrication, logistics and design, to those who implemented digital solutions.   

“The combination of my leadership role and the overall determination of the team to beat the record was what made the project a success,” he said.

Mr Allan Tan

Mr Allan Tan, Managing Director, United Tec Construction Pte Ltd


The PPVC method also sped up the building process. It took about 18 months to complete each tower, at least seven months shorter than conventional methods.

It was also especially effective during the pandemic. There was very little disruption as they were able to coordinate the manufacturing of modules that were fabricated offshore and their installation on-site in Singapore promptly while complying with each country’s safety measures.

What posed a challenge compared to traditional projects, was the need for careful planning for a seamless, efficient production to installation process. With meticulous scheduling, the ASR project was able to overcome most of the supply disruption challenges during the COVID period.

In line with the Singapore government’s net-zero carbon targets, the project adopted Pan-United Corporation’s CarbonCure, an environmentally friendly type of concrete that reduces 50 per cent carbon emission from construction material. This has raised the profile of both United Tec and Pan-United.

Another partnership was struck with Schindler Lifts. The Swiss-based company asked if Mr Tan was willing to try out its Robotic Installation System for Elevators (R.I.S.E), and he agreed.

Instead of having workers carry out tasks, the robot can drill holes and set the elevators’ anchor bolts quickly and systematically. “This has created a lot more confidence in the industry to adopt more robots to do other things too,” noted Mr Tan.

Both the PPVC and robot installation methods not only boost productivity with more efficient processes, but also offer safer working conditions– making the BE field much more attractive to younger Singaporeans.

Collaboration leads to extraordinary efforts

Property group UOL, United Tec’s client for the ASR building project, was also a great supporter. “They fully understand PPVC and its marketing requirements,” said Mr Tan.

They conveyed the right information on the project’s features when making a sale, trusted United Tec’s choice of partnerships and made payments promptly.

The Building and Construction Authority (BCA) played a major part in the project too. They helped United Tec expedite Building Innovation Panel (BIP) approvals to implement PPVC systems and abide by industry regulations.

In terms of financial cost, the construction company benefited from BCA’s PIP scheme that co-funds up to 70% of the cost for the adoption of Integrated Digital Delivery that improves the planning and execution at construction sites.

To build world record-breaking projects, all kinds of support are crucial, acknowledged Mr Tan, adding: “Only with this combined effort could we create something extraordinary.”

This has also attracted attention from overseas manufacturers, who are keen to collaborate with or seek advice from United Tec on PPVC projects abroad. “The ASR project has put Singapore on the world map for construction technology,” he noted.

On overcoming challenges when starting something new or unfamiliar, like PPVC in ASR’s case, he advises firms to be bold in adopting innovations. “If a four-year-old firm can be successful, it is also possible for others to do the same,” he said.


The Building and Construction Authority (BCA) champions the development and transformation of the built environment sector, in order to improve Singapore’s living environment. BCA oversees areas such as safety, quality, inclusiveness, sustainability and productivity, all of which, together with our stakeholders and partners, help to achieve our mission to transform the Built Environment sector and shape a liveable and smart built environment for Singapore.