An overhead link bridge that connects two buildings sitting on opposite sides of a road may sound simple to build, but ask any engineer and he will tell you that it takes a lot of precise engineering calculations to make it happen.

Add conserved buildings - whose facade must not be meddled with - to the mix and the already complicated job becomes exceedingly challenging.

Such was the situation Mr Aaron Foong, managing director of KTP Consultants, a member of Surbana Jurong Group, found himself in at the start of 2018.

His team was tasked with designing and constructing a 20m-long overhead bridge to connect Maxwell Chambers Suites - formerly known as Red Dot Traffic Building - to Maxwell Chambers across the street.

Mr Foong's solution? A novel Z-profile steel brace.

When bonded with the integrated frame on the facades of the buildings, the Z-profile steel brace could support both existing loads and that of the overhead link bridge without requiring any modifications to the facades.

For his innovative solution, the 40-year-old will be one of four professional engineers to be awarded the Building and Construction Authority's (BCA) Design and Engineering Safety Award this year.

The four award winners were announced by the BCA yesterday. The award recognises professional engineers and their teams for their innovative designs and engineering solutions to challenging projects.

"It is a sustainable way to achieve an elegant outcome," said Mr Foong, whose team decided to eschew the more "common" way of using steel beams to prop up the bridge.

"We could easily have added an additional column but it would not have matched the final intent of preserving the heritage of the two buildings, which was important to us."

Both buildings were granted conservation status by the Urban Redevelopment Authority in 2007.

While the whole project took 1½ years to complete, the installation of the overhead link bridge was done in one night to minimise traffic disruption.

Another winning project that had to be completed fast and with minimal disruptions was the Singapore Management University (SMU) Connexion, a net-zero energy teaching block in the city.

Mr Kam Mun Wai, 53, senior executive director of Meinhardt Singapore, took on the challenge and completed the project - from piling to construction to interior design works - in 15 months.

The professional engineer was given the award for his use of an innovative hybrid steel and cross laminated timber (CLT) system, which uses prefabricated modular column-beam steel frames for the main building structures.

Mr Kam said the system offered a "quick and efficient" installation process and could mitigate the challenges of on-site space constraints.

A similar hybrid steel-CLT solution was used in building a two-storey link building which connects SMU Connexion to the School of Law over the busy Fort Canning Link carriageway.