Construction In Practice 1 Individual Report Assessment 1 PDF

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This assessment is a report on modular construction within Australia.
For this report I received a mark of 17/20...

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Construction In Practice 1 Individual Report

(Modular Construction, 2020)

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Contents Executive Summary....................................................................................................................................... 3 Introduction .................................................................................................................................................. 4 Precast Concrete Panels ............................................................................................................................... 5 Associated Costs ....................................................................................................................................... 5 Advantages................................................................................................................................................ 6 Disadvantages ........................................................................................................................................... 6 Modular Components (Completed rooms)................................................................................................... 7 Associated costs ........................................................................................................................................ 8 Advantages................................................................................................................................................ 8 Disadvantages ........................................................................................................................................... 8 Conclusion..................................................................................................................................................... 9 Bibliography ................................................................................................................................................ 10

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Executive Summary Modular construction in the current Australian and Western world building industry can play a vital role moving forward. Within Australia about 5-6% of construction is classified as modular construction while in Sweden 84% of detached houses use some form of Modular Construction. Within this report a brief explanation of manufacture is discussed along with a cost comparison of Modular construction to Traditional construction methods as well as some advantages and disadvantages.

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Introduction The purpose of this report is to assess different types of modular construction for high rise multiresidential construction. There are many factors to take into consideration when choosing modular building as they each have their advantages and disadvantages, this could be lead times, cost, and suitability of choosing modular construction. Looking at different elements I have chosen to write about are prefab concrete panels, modules which are basically competed rooms that are joined on site to complete the building. As mentioned in the article, Development of performance criteria for sustainability evaluation of modular versus conventional construction methods (2016) “Modular construction has been recognized as one of the primary methods for sustainable off-site construction in the recent past. However, in a given building project, the process of selecting a suitable construction method among different options is still made based on anecdotal evidence. Thus, it is imperative to evaluate the life cycle sustainability of different construction methods.” There are many hurdles that can be encountered along the way for choosing modular construction these may be sourcing the end product and logistical issues with transporting some of these products to site. While overall there is lower environmental impacts for choosing Modular construction, it may not always be the most practical method of construction. Modular construction is a term used to define different prefabricated components, generally components are manufactured in factories and once completed are transported to site. With no codes or guides been written for the design of Modular Construction previous to May 2017 Monash University along with the Victorian Government and the support of industry bodies such as Engineers Australia, the Australian Steel Institute and PrefabAUS have written a handbook that was published May 2017 to provide guidelines on best practice for Modular Construction. (Built Offsite, 2017) Looking at modular construction on a world scale according to Global Construction Review (2015) Sweden is the world leader in modular construction with 84% of detached houses using prefabricated timber elements. Whereas developed economies such as Australia, the UK and the US, have no more than 5% of permeant housing uses any significant prefabrication. According to a report by McKinsey & Company, Modular construction: From projects to products (2019) Modular construction can be sped up by as much as 50%, with cost savings of 20%. Skilled labour and housing shortages are the biggest factors driving the demand for Modular construction. This is more apparent in Australia, UK, Singapore and the US west coast. McKinsey believe that by 2030 Modular construction in the US and Europe could have a market share to the sum of $130B with predicted cost savings of $22B annually. For all this to come to fruition changes will need to happen a few of these are, Manufactures will have to upscale and become more efficient, the Public Sector will need to amend the building codes and regulations and Investors will need to seek to understand new investment opportunities.

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Precast Concrete Panels Precast Concrete panels are formed concrete panels that are manufactured in a factory, there are various types of precast concrete panels available to the market. As per Austral precast “using state of the art technology, Austral Precast produces a diverse range of customised walling, flooring, framework, stair, balcony, and client specific precast solutions. (2020) From Austral’s brochure we can see for Modular construction there are many options available to builders across Australia to incorporate premade concrete products into their projects. These panels are manufactured in a controlled environment to ensure the drying rates of the concrete are optimal, this increases the strength and the durability of the end product. Precast concrete can be cast to various shapes and sizes with the only restraint being an appropriate size for transport.

Associated Costs Looking at a cost comparison of precast concrete compared to concrete that is cast in-situ. As stated by Chan (2011)in the Report Comparison of Precast construction costs – Case studies in Australia and Malaysia, Yong (2010) studied the financial costs between Australia and Malaysia there are significantly higher site labour costs associated with 3 elements these were the manufacture and supply of the raw or finished product, site labour and crane rental. Table 1 Comparison of Precast costs v In-situ in Australia and Malaysia Australia Malaysia Case Study Items Unit cost (AUD, %) Unit cost (RM, AUD, %) (per sq.m) (per sq.m) Precast System (Slab and Beam) AU$ 416 (100%) RM 411, AU$ 129 (100%) - Manufacture and Supply of Materials AU$ 302 (73%) RM 360, AU$ 113 (88%) - Site Labour AU$ 63 (15%) RM 23, AU$ 7 (6%) - Crane Rental AU$ 51 (12%) RM 28, AU$ 9(7%) In-situ P/T or RC Suspended Slab and Beam AU$ 539 (100%) RM 250, AU$ 78 (100%) - Supply of Materials and Forms AU$ 356 (66%) RM 175, AU$ 55 (70%) - Site Labour AU$ 126 (23%) RM 59, AU$ 18 (24%) - Crane Rental AU$ 56 (11%) RM 16, AU$ 5 (6%) Precast concrete panels can be constructed with supplementary cementitious materials such as fly ash and slag both these materials are by-products of the manufacturing industry and can help reduce the natural resources need to manufacture the panels, in turn this reduces the embodied energy needed to manufacture the panels.

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Figure 1 Precast concrete panels on a finished building

Advantages 1. 2. 3. 4. 5. 6.

Very rapid speed of erection. Good quality control. Entire building can be precast, walls, floors, beams, etc. Rapid construction on site High quality resulting from controlled conditions in the factory. Prestressing is easily done which can reduce the size and number of structural members required.

Disadvantages 1. 2. 3. 4. 5. 6. 7.

Very heavy members Camber in beams and slabs Very small margin for error Connections may be difficult Somewhat building design flexibility Joints between panels are often expensive and complicated Cranes are required to lift the panels

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Modular Components (Completed rooms) What are Modular Components? Modular components are a more advanced type of modular construction, these modules are completed rooms that are furnished within a factory. Although modular construction is not a new technique of building, it is relatively a new form of construction in the high rise market as there are a lot more complex issues. These issues could be that each piece has minimal tolerances to work on site and must be fitted exactly to avoid creeping. (Velamati 2012) These components are then transported to site where they are lifted into place and fixed off to form the structure. Modular construction has minimal requirements needed for on site manufacture. This is usually joining the modules together to form the structure, other elements like External cladding are install on site at a later date. Reductions in time and cost are the biggest benefit with prefabricated modules, there are also improved quality and accuracy in manufacturing. The speed of installation is also quick, and this type of module can be dismantled and reused. The environmental benefits for this type of construction are a reduction of construction waste, less noise pollution to neighboring properties along with dust minimization. (Navaratnam et al. 2019) It is estimated using this type of modular building technology, construction schedules can be reduced by 30% to 50% than traditional construction methods. In figure 2 below a quick comparison shows the reduction in time from Modular built to traditional construction. (Modular.org 2020)

Figure 2 Time savings between Modular construction and Traditional site built construction.

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Associated costs The costs associated for modular building to traditional building as written by Sri Velamati in 2012 seen in table 2 below is a guideline based on a 20+ storey, 397 apartment building with a high level of finishes applied. The table shows there is a minimal variation in price between the two, but the time savings which are not specified would outweigh the money saved on a project of this size. Table 2 Comparison of costs between Modular construction and traditional construction.

Advantages 1. 2. 3. 4. 5. 6.

Lower development or business process costs Production costs Maintenance Wooden prefab houses can have lower heating requirements Speed of manufacture Less building waste

Disadvantages 1. 2. 3. 4.

Room size limitations Limited design options Reduced resell value Difficult to Finance

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Conclusion This report discusses two types of modular construction that can and are used in the construction sector worldwide. Both of the chosen styles are different within their construction method but the end goal is a reduction of building waste, less time needed for construction and the bottom line lower costs associated with building. While Precast concrete panels are a more common type of construction in the current building climate. Precast is an economical and viable method moving forward as the costs, and time savings outweigh a conventional method of construction. While it may not be as common to construct large multi residential building there are positive impacts not just on the environment. Modular components like Lego bricks have their limitations of uses in the construction industry. While there will always be some required on site work to finish building off while using modular components, being manufactured in a factory environment the construction period of onsite work is less and the amount of construction waste is also minimal. Overall the building industry is looking at minimizing skilled labour, financial impacts and regulations required to build large scale projects, with Modular construction there are many positives moving forward as a handbook written by Monash University and the Victorian Government can allow builders and Investors insight into the requirements of Modular Construction.

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Bibliography Title page image, Modular construction – an alternative construction, igr news, viewed 27 August 2020, Austral Precast, Austral Precast building solutions, Salisbury, QLD. Bertram, N, Fuchs, S, Mischke, J, Palter, R, Strube, G, Woetzel, J, 2019, Modular construction: from projects to products, viewed 22 August 2020,

Chan T K (2011) Comparison of precast construction costs – case studies in Australia and Malaysia In: Egbu, C. and Lou, E.C.W. (Eds.) Procs 27th Annual ARCOM Conference, 5-7 September 2011, Bristol, UK, Association of Researchers in Construction Management, 3-12, viewed 23 August 2020. Kamali, M, Hewage, K, ‘Development of performance criteria for sustainability evaluation of modular versus conventional construction methods’, Journal of cleaner production, vol. 142, no. 147, pp. 3592-3606, viewed 22 August 2020. Modular construction code board handbook a guide to offsite construction, built offsite, 2017, viewed 27 August 2020, Velamati, S 2012 Feasibility, benefits and challenges of modular construction in high rise development in the United States: a developer’s perspective, thesis, Massachusetts Institute of Technology, viewed 26 August 2020. What is modular construction, modular building institute, viewed 23 August 2020,

Why Sweden beats the world hands down on prefab housing, Global construction review, viewed 25 August 2020, Yong, T. N. (2010), Feasibility of Precast Concrete Construction System in Malaysia: A Comparative Study between Australia and Malaysia, Research Project Report, The University of Melbourne, Australia.

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