As mentioned by the Chief Executive in the 2020 Policy Address, Hong Kong will strive to achieve carbon neutrality before 2050. To this end, the Government will examine various means and take forward different measures to reduce carbon emissions. Against this background, the Environment Bureau and the Electrical and Mechanical Services Department have been spearheading the implementation of District Cooling System (DCS) in new development areas, including Tung Chung New Town Extension (East) and Kwu Tung North New Development Area.
The Finance Committee of the Legislative Council recently approved the DCS funding proposals for Tung Chung East (HK$3,918.2 million) and Kwu Tung North (HK$5,787.7 million) in February 2021. Both projects involve DCS pipe laying, as well as the design, construction and operation of DCS plants, and aim to provide district cooling services commencing from around 2026 to meet the population intake schedules.
DCS is a large-scale centralised air-conditioning infrastructure which creates green job opportunities and reduces the heat island effect. It is more energy efficient than the traditional central air-conditioning system in individual buildings and achieves energy saving by taking advantage of economy of scale and load diversity of various buildings.
This article is contributed by the Environment Bureau and the Electrical and Mechanical Services Department, the HKSAR Government
Designed by Herzog & de Meuron in partnership with TFP Farrells and Arup, the long-awaited M+ has completed its construction of museum building and is set to open to the public by the end of 2021.
With a total footprint of 65,000 sq m, the M+ building houses 17,000 sq m of exhibition space across 33 galleries. Its eye-striking inverted T shape is a simple design, yet its façade is something special. The podium and tower are united as concrete structures clad in ceramic tiles that reflect the changing conditions of light and weather. The tower is covered with 140,000 pieces of ceramic tiles, many with windows in between. They are laid out in a horizontal louvre structure to provide sun shading to the museum’s interior spaces.
The M+ building sits directly above tunnels for the MTR Airport Express and Tung Chung Line. The excavation around the railway tunnels produces a ‘found space’ that provides an anchor for the building for hosting dynamic and rotating installations. To facilitate the construction, the project team needed to control the tunnel movements in accordance with strict limits set by Hong Kong’s transit and building authorities. The engineering solution included the use of five mega-trusses which prevent the massive structure loading on the tunnels.
The landmark building also includes three cinemas, a mediatheque, a learning hub, a research centre, a roof garden, a members lounge, a coffee and tea bar, museum shops, restaurants and offices, providing a space for learning, interpretation and inspiration set against the backdrop of Victoria Harbour.
This article is contributed by Arup.
I am glad to learn about the achievements in the application of Modular Integrated Construction (MiC) from the Cover Story in Hong Kong Engineer of January 2021 (Volume 49). However, in my opinion, the concept of Modular Construction has not been presented in a balanced manner.
The article has used the terms “MiC” and “Modular Construction” interchangeably, creating the impression that both are the same. In fact that is not the case. Modular Construction represents a family of solutions that embraces off-site manufacturing and on-site assembly. On the other hand, MiC, which mandates the use of freestanding volumetric modules manufactured off-site according to the definition of the Development Bureau, is only one member of the family.
According to a report titled “Modular Construction: From projects to products” published by McKinsey & Company in June 2019, Modular Construction “involves producing standardised components of a structure in an off-site factory, then assembling on site.” These components can be three-dimensional (3D) volumetric units or two-dimensional (2D) panels. While 3D volumetric solutions involving fully-fitted units (ie MiC) maximise productivity benefits, 2D panelised solutions (an analogy is the assembly of Ikea furniture) optimise logistics in transport and storage. There are advantages and limitations associated with each approach. The report concludes that the specific requirements, circumstances and constraints of a project determine whether a 3D volumetric solution, a 2D panelised solution, or a hybrid solution offers the best option. There is no one-size-fits-all solution.
Today, Modular Construction represents a forest of opportunities to the building industry. MiC is probably the most eye-catching tree in this forest. While driving wider application of MiC in Hong Kong, it is important for our industry leaders to keep an open mind and not let the focus on a big tree block the view of the lush forest behind it.
Ir Alan H L MAN
I am grateful to you for forwarding the views of Ir Alan Man about the Cover Story published in the January 2021 issue of Hong Kong Engineer which is entitled “Modular Integrated Construction for High-rise Buildings: Measured Benefits” (DEVB et al., 2021), and would like to provide my responses hereinafter.
First of all, let us get the concept fundamentally correct. MiC was developed in Hong Kong building on the Modular Construction (MC) approach which has been widely adopted globally, while MiC emphasises the integration of advanced manufacturing technologies into the re-engineered building and construction processes particularly for high-rise developments in high-density contexts. As mentioned in the Cover Story, the concept of MiC was defined by Pan and Hon (2018) as:
“a game-changing disruptively-innovative approach to transforming fragmented site-based construction of buildings and facilities into integrated value-driven production and assembly of pre-finished modules with the opportunity to realise enhanced quality, productivity, safety and sustainability.”
The Development Bureau Technical Circular (Works) No 2/2020 described MiC in a more concrete form as:
“a construction method whereby freestanding volumetric modules with finishes, fixtures, fittings, furniture and building services installation, etc manufactured off-site and then transported to site for assembly.”
MC is the most advanced off-site construction technology with three-dimensional units that enclose usable space and are often prefinished. Various terminologies have been used in different countries and regions for the MC approach, with examples including “modular building” in the UK (Gibb and Pendlebury, 2006),“permanent modular construction” in the US (MBI, 2013), “Prefabricated Prefinished Volumetric Construction (PPVC)” in Singapore (BCA, 2017), and of course “Modular Integrated Construction (MiC)” in Hong Kong. There are subtle differences between these terms, which are explained and illustrated in the Glossary produced by the Centre for Innovation in Construction and Infrastructure Development (CICID) of The University of Hong Kong (HKU) (Pan et al., 2020). However, such differences should not concern the adopters of MiC in Hong Kong or MC in the global context. Nevertheless, there is a fundamental difference between MiC or MC and off-site construction. The latter is a term literally developed to contrast with on-site construction, and covers a wide spectrum of off-site technologies including MC. There exist in market at least hundreds of off-site technologies, components and systems manufactured and supplied by thousands of factories. Prof Alistair Gibb and his team from Loughborough University, UK developed a level system to have categorised the many off-site technologies at four levels (Gibb 1999; Gibb and Pendlebury, 2006), ie:
- Level 1 “component subassembly” (eg prefabricated lintels),
- Level 2 “non-volumetric preassembly” (eg precast wall panels),
- Level 3 “volumetric preassembly” (eg bathroom pods), and
- Level 4 “complete buildings”.
For details one may refer to Prof Gibb’s seminal monograph entitled “Off-site Fabrication: Prefabrication, Pre-assembly and Modularisation” published in 1999 and Loughborough University’s off-site glossary of terms published in 2006 (Gibb and Pendlebury, 2006). One may further refer to the Glossary of MiC produced by the CICID of HKU in 2020 (Pan et al., 2020), which expands the off-site construction terms to also cover MiC as well as smart construction in line with the global trend of the construction industry towards modularisation and digitalisation.
However, despite the well-established body of knowledge of MiC, MC and off-site construction, there still exist misunderstanding of individuals and organisations about the terms. Ir Man brought forward the report published by McKinsey & Company (2019). Although the term “modular construction” is used in the title of that report with no reason provided perhaps as an eye-catcher, many terms are used in the report interchangeably with no definition or description provided. The terms used in that report include:
“modular construction” (title and throughout), “modular (or prefabricated) construction” (Page 1), “prefabricated housing” (Page 1), “pre-fabricated components” (Page 5), “prefabricated buildings” (Page 17), “industrial construction” (Page 18), “offsite manufacturing” (Page 19), “offsite construction” (Page 22), “offsite-produced residential buildings” (Page 23), “modular prefabrication” (Page 23), etc. In addition to the inconsistent and somehow improper use of these terms, that report also wrongly states “Terms such as offsite construction, prefabrication, and modular construction are used interchangeably” (Page 7) which should be corrected. What is illustrated in the figure (Exhibit 2, Page 8) actually shows the spectrum of off-site construction technologies, but not “modular construction” incorrectly put in the figure caption. The body of literature of off-site and MC should have been properly accessed to avoid misunderstanding.
Next comes my response to the metaphors of “tree” and “forest” given by Ir Man, although such response might be considered no longer needed after the misunderstanding becomes self-evident and demystified. Hong Kong has witnessed a general high-speed development mode in the past half a century. That was partly attributed to the development and application of many innovations and technologies such as precast concrete technology for public housing development. This technology undoubtedly contributed significantly to the housing supply in the city, enjoying the cheap labour and policy support in the then Pearl River Delta now called the Greater Bay Area (GBA). Nevertheless, sacrifices came along such as the loss or at least insufficient retention of intellectual properties affiliated with the reallocated manufacturing capabilities outside Hong Kong and the lack of procurement bargaining power due to the increasingly rigid supply chains, which are coupled with the threats of the rising labour cost in the GBA and the shifting focus of the manufacturing industry in the GBA towards the domestic market driven by the national “dual circulation” strategy. In particular, off-site construction has been a national policy in recent years, inspiring a large number of innovations and technologies for not only off-site itself but also green and digital, widely perceived to be leaving the counterpart practices in Hong Kong well behind. MiC is a disruptive innovation developed in Hong Kong and, despite its introduction only since 2017, has already demonstrated its rich benefits for and vigorous life in Hong Kong development. As of February 2021, there had been 31 MiC systems granted with the Buildings Department’s in-principle acceptance and dozens of MiC projects completed or under planning, design or delivery in Hong Kong. This is a competitive edge that the Hong Kong construction industry should firmly grasp and fully capitalise on. Nevertheless, it is wise not to overstate MiC as a panacea, now or ever. Different types of off-site construction technologies at the four levels listed above have their own merits and applicability, eg for buildings and infrastructures. This is further elaborated below.
At the HKIE Building Division Annual Seminar on 8 April 2019 I had an opportunity to explain the relation between MiC and off-site construction, eg that MiC is the highest level of the off-site construction spectrum, hence game-changing and disruptive rather than incremental (Pan, 2019). MiC should be promoted to spearhead the innovation and technology breakthrough and diffusion in Hong Kong construction. Shortly after that on 28 May 2019, the CICID of HKU launched the MiC Strategy Paper entitled “Modularisation for Modernisation: A Strategy Paper Rethinking Hong Kong Construction”, in which we defined the three words of MiC as:
“The term ‘modular’ is defined herein as the process of modularising fragmented site-based construction elements, components and facilities to integrated prefinished modules to best suit value-driven production and assembly, and should not be simply understood as 3D volumetric modules per se.
The term ‘integrated’ is defined herein as the process of integrating different construction activities and players in the vertical design and supply chains and of integrating various functions and stakeholders in the lateral institutional settings. The integrated process should reflect the progressive approach to promoting MiC in various construction sectors such as hostel, hotel and housing in an appropriate roadmap to address their strengths, weaknesses, opportunities and challenges. The integrated process should also avoid regarding MiC as a technical approach per se, but embrace it within the legislative, economic, social, and technological contexts.
The term ‘construction’ is defined herein as the life cycle based whole process covering planning, design, production, construction, facility management, but not site construction per se, so as to allow pre-site virtual building engaging BIM for mitigated risks and post-site smart feedback engaging IoT for enhanced accountability.” (Pan et al., 2019, Page 23)
With the definitions set forth above, the MiC approach should easily find its solid ground in infrastructures too, and open up new opportunities for various off-site construction technologies.
Hong Kong construction has surely rich strengths but also clear weaknesses, and golden opportunities but also alarming threats, in the face of the changing climate of the city itself, the GBA and globally. What is perceived as “the lush forest” in Ir Man’s views might become a barren land - not the “barren rock with hardly a house upon it” remarked in the colonial history - but one with little inspiring innovation which would certainly mismatch the highly ranked infrastructure and development of the city. Thus, here comes a golden time for us to fully embrace innovation and technology spearheaded by MiC, and probably the only time.
Last but not the least, I would like to reiterate the “MiC Innovating Higher” model that covers the four themes of “higher-rise, higher-density, higher-tech, and higher-co-creation” for the future MiC development, which the HKIE Building Division offered me to present at its Annual Seminar in 2019. This model became the theme of the International Conference on MiC organised on 27 August 2019 and honoured by the Chief Executive of the HKSAR. It is good to “keep an open mind” but only when there is yet any focal point. However, clearly now we have got one, and needed is MiC to spearhead at full pace.
Ir Professor Wei PAN
Centre for Innovation in Construction and Infrastructure
Department of Civil Engineering
The University of Hong Kong
- BCA (2017). Prefabricated Prefinished Volumetric Construction (PPVC) Guidebook. Building and Construction Authority (BCA), Singapore.
- DEVB, ArchSD, HKSTP and HKU CICID (2021). Modular integrated construction for high-rise buildings: measured benefits. Hong Kong Engineer, Vol 49, Jan 2021, pp.10-17.
- Gibb, A. G. F. (1999). Off-Site Fabrication: prefabrication, preassembly, and modularisation. Whittles Publishing.
- Gibb, A. G. F. and Pendlebury, M.C. (2006). Glossary of Terms . Buildoffsite, London.
- MBI (2013). Permanent Modular Construction 2013 Annual Report. Modular Building Institute (MBI).
- McKinsey & Company (2019). Modular construction: From projects to products. McKinsey & Company: Capital Projects & Infrastructure.
- Pan, W. (2019). Modular Integrated Construction: Innovating Higher. Proceedings of HKIE Building Division 18th Annual Seminar, 8 April 2019, Hong Kong.
- Pan, W. and Hon, C. K. (2018). Modular Integrated Construction for High-rise Buildings. Proceedings of The Institute of Civil Engineers - Municipal Engineer, DOI: 10.1680/jmuen.18.00028.
- Pan, W., Yang, Y., Zhang, Z. and Chan, S. (2019). Modularisation for Modernisation: A Strategy Paper Rethinking Hong Kong Construction. CICID, The University of Hong Kong, Hong Kong. https://www.miclab.hk/mfm.
- Pan, W., Zhang, Z. and Yang, Y. (2020). A Glossary of Modular Integrated Construction. The University of Hong Kong, Hong Kong. ISBN 978-962-8014-27-9. http://hdl.handle.net/10722/297012.