Summary Reader Response Draft 4

The guidebook titled, “Design for Manufacturing and Assembly (DfMA) Prefabricated Prefinished Volumetric Construction” released by the Building and Construction Authority of Singapore (BCA) (2017) explains the features of Prefabricated Prefinished Volumetric Construction (PPVC), a construction method that heavily involves off-site construction. Construction modules that consist of several units are manufactured in factories complete with interior finishes such as walls or toilet fixtures. The modules are then transported to the site and installed onto the building in a “Lego-like” (BCA, 2017, Introduction section, para. 3) manner. In accordance with Hwang et al. (2018), PPVC is unique as compared to other construction methods as construction can be done concurrently, saving cost and time. PPVC has gained popularity worldwide due to this reason and university campuses in the United States have adopted PPVC as a way to build dormitories or classrooms efficiently (Hwang et al., 2018). In Singapore, PPVC is the main approach in constructing buildings such as HDB flats and university dormitories. One such example is the North Hill Residential Halls of Nanyang Technological University, as mentioned in the Global Brands Magazine website (“NTU builds Singapore’s”, 2018). BCA has been encouraging PPVC as the main form of construction in Singapore even making it mandatory for certain land parcels under the “Government Land Sales Program” (Hwang et al., 2018, p. 170).

PPVC should be encouraged by the Singapore government due to its clean means of construction and increased productivity. However, critics argue that its high initial cost of construction could deter cities from employing PPVC as a construction method.

PPVC should be encouraged by the government due to its clean means of construction. According to Pons et al. (2011), the built environment industry causes environmental damage due to its usage of non-renewable fuel sources and its inability to recycle materials. In traditional on-site construction, materials are used with the intent of using them once. After the building has surpassed its use, construction materials will go to waste. Cast insitu buildings cannot be dismantled and can only be demolished. Once demolished, there is rarely any use for the remaining demolished materials and thus they will end up in land fills. According to a construction waste management proposal document written by the European Commission (2015), Spain produced 27 million tons of construction waste in 2012 and 32% of this waste end up in landfills. In contrast, the National Environmental Agency of Singapore (NEA) (2022), reported that Singapore has a combined construction waste of 1,421 tons. However, almost 99 percent of this waste are recycled. This is due to good recycling practices in Singapore as well as the high usage of PPVC. Thus, if the Singapore government continues to encourage the use of PPVC in construction projects, even less construction waste will end up in landfills. Shen et al. (2011) mentioned that precast concrete slabs could be recycled when constructing temporary construction works, thus leading to cleaner means of construction. Similarly, Kang et al. (2023), reported on a new method of recycling concrete waste in Singapore by transforming waste into precast concrete walls thus reducing waste and leading to cleaner means for construction.

Another reason why PPVC should be encouraged is due to its increase in productivity. according to Ong and Yahya (2016), the use of PPVC and off-site construction allows for better productivity. On-site activities such as pouring concrete and waiting for it cure takes time. As mentioned by Ong and Yahya (2016), ‘majority of on-site activities are replaced by more efficient, faster factory processes, construction time can be shortened with the increased labour productivity’ (Ong et al., 2016, p. 70). Better productivity leads to shorter construction time and construction projects could be constructed at a faster rate saving time and money.

Despite the various advantages that PPVC offers, it does have its challenges as well. Kamali and Hewage (2016) state that high initial cost could be a reason why companies are not keen on using PPVC as a construction method. A large initial capital will be needed to source for suitable machinery and workers to run a PPVC manufacturing plant. In countries such as Singapore, companies have a large capital to be able to afford PPVC as a means for construction. However, for companies in developing parts of the world with insufficient capital, they may choose to stick to traditional on-site construction methods due to cheap labour. The lack of  professionals with experience in PPVC could also deter companies from employing the use of PPVC, which is the case in China (Chao et al., 2013).

In conclusion, there is adequate evidence to support the benefits of PPVC and why the Singapore government has been encouraging the use of it. PPVC technologies have caused a breakthrough in the construction industry due to its numerous productivity and cost benefits amongst other contributing factors. However, companies must decide carefully if they should use PPVC due to its limiting factors such as its high initial cost. Ultimately, greater implementation of modular construction methods could be highly useful in the near future and this technology could replace any weaknesses of cast in situ concrete. 

 

 

 

 

 

 

 

 

 

 

 

 

References

Building Construction Authority of Singapore (2018). Design for Manufacturing and Assembly (DfMA) Prefabricated Prefinished Volumetric Construction. https://www1.bca.gov.sg/docs/default-source/docs-corp-news-and-publications/publications/for-industry/ppvc_guidebook.pdf

European Commission. (2015, May 26). Construction and Demolition Waste management in Spain. https://ec.europa.eu/environment/pdf/waste/studies/deliverables/CDW_Spain_Factsheet_Final.pdf

Hwang, B.-G., Shan, M., & Looi, K. Y. (2018). Knowledge-based decision support system for prefabricated prefinished volumetric construction. Automation in Construction, 94, 168-178. https://www.sciencedirect.com/science/article/abs/pii/S0926580517311044

Kang, J., Ng, Y. B., & Phua, W, L. (2023, Mar. 02). Joe Green makes concrete go green. The Business Times. https://www.businesstimes.com.sg/singapore/smes/joe-green-makes-concrete-go-green

Kamali, M., & Hewage, K. (2016). Life cycle performance of modular buildings: A critical review. Renewable and Sustainable Energy Reviews, 62, 1171–1183. https://www.sciencedirect.com/science/article/abs/pii/S1364032116301411

Mao, C., Shen, Q., Pan, W., & Ye, K. (2013). Major Barriers to Off-Site Construction: The Developer’s Perspective in China. Journal of Management in Engineering, 31(3). https://ascelibrary.org/doi/full/10.1061/%28ASCE%29ME.1943-5479.0000246?casa_token=cQxIsKN0PEgAAAAA%3AavSntlunI7HY2rREf9vfZnKB1M9seHryy9LLQ7ct4Nyi91dxnoHhFRumgT7jDuB1C1Sy-ykYRyeYkdA

NTU builds Singapore’s first “Lego-style” high-rise residences. (2016, January 12).  Global Brands Magazine. https://www.globalbrandsmagazine.com/ntu-builds-singapores-first-lego-style-high-rise-residences/

National Environmental Agency of Singapore. (2022). Waste Statistics and Overall Recycling. https://www.nea.gov.sg/our-services/waste-management/waste-statistics-and-overall-recycling

Pons, O., & Wadel, G. (2011). Environmental impacts of prefabricated school buildings in Catalonia. Habitat International, 35(4), 553-563. https://www.sciencedirect.com/science/article/abs/pii/S0197397511000191

Rui, O. Y., & Yahya, K. (2016). The Productivity Rate of Prefabricated Pre-Finished Volumetric Construction (PPVC). https://civil.utm.my/wpcontent/uploads/2016/12/The-Productivity-Rate-of-Prefabricated-Pre-Finished-Volumetric-Construction-PPVC.pdf

Shen, L., Tam, V. W., & Li, C. (2009). Benefit analysis on replacing in situ concreting with precast slabs for temporary construction works in pursuing sustainable construction practice. Resources, Conservation and Recycling, 53(3), 145–148. https://www.sciencedirect.com/science/article/abs/pii/S0921344908001997?fr=RR-2&ref=pdf_download&rr=855dba085e3c1904