HDB pilots advanced construction technologies to design and build flats

In a further push to raise construction productivity, HDB has set a new target of 40% site productivity improvement by 2030, building on the 25.9% improvement achieved in 2020, over the baseline year of 2010.

The Housing & Development Board (HDB) will be accelerating its push towards higher construction productivity in public housing projects, with a new target of 40% site improvement by 2030, even as it delivers quality homes to Singaporeans. This comes on the back of sustained productivity improvements for public housing projects over the last more than two decades. In 2020, HDB achieved a 25.9% productivity improvement, exceeding the target, set in 2010, to achieve a 25% improvement by 2020.

Since 2021, the adoption of Design for Manufacturing and Assembly (DfMA) in all new HDB projects, as well as Integrated Digital Delivery (IDD) in some projects, has continued to contribute to productivity growth.

A key initiative in meeting HDB’s new target is a Construction Transformation Project (CTP) which will pilot a range of innovations and technologies to further raise productivity.

In partnership with construction firm, Obayashi Singapore Pte Ltd, HDB will adopt the latest advanced construction technologies, to design and build the upcoming Garden Waterfront I & II @ Tengah Build-To-Order (BTO) project.

When completed, the CTP aims to realise a 25% improvement in productivity as compared to other BTO projects then.

HDB’s Chief Executive Officer, Mr Tan Meng Dui said, “The pandemic, over the past two years, posed tremendous challenges to the building industry, not least in terms of workers shortage and supply chain resilience. As the largest housing developer in Singapore, HDB is keenly aware of our role as a catalyst and market mover in driving construction productivity and transformation of the Built Environment sector. Our efforts in harnessing technology, including DfMA and IDD, have enabled us to continually improve productivity over more than two decades, and this continued even in 2021 when productivity improvements reached 26.2%. With the CTP, we hope to raise the bar further and find novel ways to construct quality homes, with less manpower, faster and safer. These efforts, which are geared towards achieving construction productivity improvements of 40% goal by 2030, will also enhance the resilience of our construction ecosystem, and support the ramp-up of HDB’s building programme over the next few years and deliver HDB flats faster to our buyers”.

The Construction Transformation Project

The Construction Transformation Project (CTP) at Tengah seeks to transform the way HDB designs and constructs flats. To this end, HDB will break new ground in advanced prefabrication, pilot new technolo- gies in automation, and implement innovations that make for more efficient construction management. Key takeaways from this project will be studied for future implementation in other BTO projects.

KEY STAGES AND CHANGES

HDB will adopt new technologies and innovations for the design, fabrication, and construction stages of the CTP.

Design

HDB will use Virtual Design and Construction (VDC) to simulate the design and construction activities virtually, so that they can be refined further by consultants and contractors, before the actual construction on site. This allows greater integration and collaboration among stakeholders across the construction value chain.

One main component of VDC is the virtual mock-up unit – a digital twin of the actual residential unit, with a high level of detail, such as the positions of pipes, sanitary fixtures, power points, switches, and furniture. This gives the project team an ‘X-ray vision’ of the unit, enabling the team to identify and resolve potential design and construction issues upstream, collaboratively. Previously, life-size physical mock-ups of the kitchen and toilet, using plywood, i.e. timber mockups, had to be built, and this took up more time, effort, and resources. All new HDB projects launched from 2022, including the CTP, will use virtual mock-ups instead of timber mock-ups.

Fabrication

Hybrid precast system

Currently, full 3D Prefabricated Prefinished Volumetric Construction (PPVC) components are used in many HDB projects. For the residential units in this CTP, HDB will be using a more efficient, hybrid system that includes both 2D and 3D precast components.

Beamless flat plate system

The hybrid precast system will enable HDB to design and build residential units, using a beamless flat plate system, which results in consistently higher headroom compared to flats in typical BTO projects, which have beams. As a result, residents will have greater flexibility in configuring the layout of their flats.

3D concrete printing

HDB is currently piloting the use of 3D concrete printing for small streetscape furniture and other landscape features, for some projects in Tengah and Bidadari. For the CTP, HDB will be going one step further, by using a special, fibre-glass reinforced concrete material to provide structural strength. This innovation allows HDB to potentially use less material than conventional 3D printing methods. This also paves the way for studies on larger and more complex structures that can be potentially fabricated in this manner, without the need for complex moulds.

Construction

To allow for cleaner, higher quality and less manpower-intensive construction, HDB will be testing a few innovations from Obayashi, on a pilot basis, to study their impact on productivity and construction safety.

The innovations

• To reduce manpower required for repetitive and labour-intensive activities, such as operating tower cranes, Artificial Intelligence (AI) will be used in tower crane operations, to optimise the hoisting routes for precast components. Light Detection and Ranging (LiDAR) will also be used to detect and avoid collisions. LiDAR is a remote sensing technology that uses light in the form of a pulsed laser to measure distances to a target.

• Currently, crawler cranes are largely operated manually. With the Crane Machine Guid- ance technology, crawler crane operators will be guided on the optimum path for lifting the elements in the construction of the multi-storey car park, using a combination of LiDAR and Building Information Modelling (BIM).

• In place of workers required to guide the components into place or to make manual adjustments using guide wires, the SkyJuster, which is attached to the end of the hoisting block, will orientate precast elements to their correct position before they are lowered into place. This helps to reduce the number of workers needed for the precast installation process.

Integrated Digital Delivery

Additionally, HDB will adopt IDD for this project. Digital technologies will be used extensively to integrate work processes and connect stakeholders throughout the various stages of the construction and building life cycle, through a cloudbased common data environment. For example, precast components will be automatically tracked using RFID or Bluetooth tags, from the time they are fabricated at precast yards, to when they are delivered to site and assembled. IDD helps to better manage the logistics planning and movement of precast components from the precast yard to the construction site, for the project.

Target Productivity Gains

The innovations in this CTP are expected to yield higher productivity, through more efficient use of manpower and resources, while reducing material wastage. Together with the use of digital technologies for tighter and more effective collaboration between project stakeholders, from design to construction, HDB has targeted a 25% improvement in productivity, compared to other BTO projects.

Deeper Collaborations

Beyond the CTP, HDB also partners researchers, Institutes of Higher Learning (IHLs) and companies, to continually explore ways to address challenges related to construction productivity and sustainability.

Two key initiatives are the Cities of Tomorrow R&D programme and the Cool Ideas Enterprise platform.

LAUNCH OF NEW GRANT CALLS UNDER THE CITIES OF TOMORROW R&D PROGRAMME

The Cities of Tomorrow (CoT) R&D Programme aims to establish Singapore as a highly liveable, sustainable, and resilient city of the future, and a vibrant urban solutions hub. HDB, together with MND (Ministry of National Development) and BCA (Building and Construction Authority), is launching new grant calls in search of innovative solutions, in the areas of advanced construction productivity, infrastructure resilience and facilities management. These will include the development of solutions to:

• Develop infrastructure to enable robotic assembly on construction sites.

• Automate inspection, diagnosis and maintenance of external building facades.

• Geo-reference and detect underground services and assets for new estates.

• Automate the collection of waste at older estates served by individual refuse chutes.

Launched in 2017, the Cities of Tomorrow (CoT) is MND’s flagship R&D programme to develop Urban Solutions and Sustainability for the Built Environment.

Cool Ideas Enterprise

HDB and Enterprise Singapore have committed another SGD 5 million to support the Cool Ideas Enterprise (CIE). The additional funding provided to the open-innovation platform will continue to support enterprises’ efforts to co-develop solutions to improve HDB living. To this end, HDB is currently calling for solutions to increase productivity and reduce manpower at construction sites and off-site facilities (e.g. precast yards), through automation or digital solutions, without compromising quality and safety.

Launched in 2018, the Cool Ideas Enterprise (CIE) is an open innovation platform for companies and innovators to co-develop solutions with HDB, to address public housing challenges. An estimated SGD 5 million funding was set aside, then. Companies, with projects supported by the CIE, will receive co-funding from Enterprise Singapore, and will have access to HDB’s technical mentorship, test-bedding facilities at HDB’s Centre of Building

Research, as well as opportunities to pilot their solutions on a small scale, in HDB towns.

Continued Partnerships With Industry

HDB values the close collaborations with industry partners to develop joint solutions or ideas that can be piloted in new housing projects. Several transformations that have been brought about in the design and construction of public housing are a result of these partnerships and cross-sharing of knowledge. These efforts will enable HDB to continue delivering quality homes and living environments.

All images by HDB, unless otherwise stated