Scholarly article on topic 'Offsite Manufacturing Construction: A Big Opportunity for Housing Delivery in Nigeria'

Offsite Manufacturing Construction: A Big Opportunity for Housing Delivery in Nigeria Academic research paper on "Civil engineering"

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Abstract of research paper on Civil engineering, author of scientific article — Shaba James Kolo, Farzad Pour Rahimian, Jack Steven Goulding

Abstract The problem of housing delivery is of great concern in many countries of the world. This problem is more predominant in developing countries and Nigeria is not an exception. In Nigeria, this challenge has been magnified as a result of myriad of issues, e.g. high population growth rate, shortage of necessary skills, disintegrated supply chain etc. Seminal literature has proven that offsite manufacturing (OSM) can help improve housing delivery efforts both in terms of quantity and quality. The purpose of the research was to investigate the current housing delivery problems in Nigeria and evaluate the feasibility of adopting OSM. To achieve this, the study conducted substantial literature review to explore the benefits of OSM, identify the problems of housing delivery in Nigeria and explore different dimensions and the issues that can be associated with using OSM in Nigeria. The results revealed that there are a good number of benefits promised by OSM; notable among these benefits are: less wastage on site, faster construction time, quality improvement and reduction in wet trades. Moreover, some of the problems of housing delivery in Nigeria identified included: skills shortage, reliance on conventional construction techniques, slow pace of construction, and low quality of housing. The study also showed that adaptation of OSM has been quite useful in other countries facing the similar issues of housing shortage, e.g. Malaysia. As such, it is argued that OSM can improve skills shortages, improve the speed of construction, improve the overall quality of housing and help eliminate wet trades. For the problems of housing delivery to be tackled in Nigeria, it is important to undertake additional research to identify the benefits, barriers and context-specific ways of adopting OSM in Nigeria.

Academic research paper on topic "Offsite Manufacturing Construction: A Big Opportunity for Housing Delivery in Nigeria"

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ScienceDirect Procedía

Engineering

Procedía Engineering 85 (2014) 319 - 327 =

www.elsevier.com/locate/procedia

Creative Construction Conference 2014, CC2014

Offsite manufacturing construction: a big opportunity for housing

delivery in Nigeria

Shaba James Kolo, Farzad Pour Rahimian*, Jack Steven Goulding

The Grenfell-Baines School of Architecture, Construction and Environment, University of Central Lancashire, Preston PR1 2HE, UK

Abstract

The problem of housing delivery is of great concern in many countries of the world. This problem is more predominant in developing countries and Nigeria is not an exception. In Nigeria, this challenge has been magnified as a result of myriad of issues, e.g. high population growth rate, shortage of necessary skills, disintegrated supply chain etc. Seminal literature has proven that offsite manufacturing (OSM) can help improve housing delivery efforts both in terms of quantity and quality. The purpose of the research was to investigate the current housing delivery problems in Nigeria and evaluate the feasibility of adopting OSM. To achieve this, the study conducted substantial literature review to explore the benefits of OSM, identify the problems of housing delivery in Nigeria and explore different dimensions and the issues that can be associated with using OSM in Nigeria. The results revealed that there are a good number of benefits promised by OSM; notable among these benefits are: less wastage on site, faster construction time, quality improvement and reduction in wet trades. Moreover, some of the problems of housing delivery in Nigeria identified included: skills shortage, reliance on conventional construction techniques, slow pace of construction, and low quality of housing. The study also showed that adaptation of OSM has been quite useful in other countries facing the similar issues of housing shortage, e.g. Malaysia. As such, it is argued that OSM can improve skills shortages, improve the speed of construction, improve the overall quality of housing and help eliminate wet trades. For the problems of housing delivery to be tackled in Nigeria, it is important to undertake additional research to identify the benefits, barriers and context-specific ways of adopting OSM in Nigeria.

CrownCopyright©2014PublishedbyElsevierLtd. This is an open access article under the CC BY-NC-ND license

(http://creativecommons.org/licenses/by-nc-nd/3.0/).

Peer-review under responsibility of the Diamond Congress Kft.

Keywords: housing delivery; housing shortage; Nigeria; offsite manufacturing;

CrossMark

* Corresponding author. Tel.: +44-1772-893-215; fax: +44-1772-892-916. E-mail address: fpour-rahimian@uclan.ae.uk

1877-7058 Crown Copyright © 2014 Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license

(http://creativecommons.org/licenses/by-nc-nd/3.0/).

Peer-review under responsibility of the Diamond Congress Kft.

doi: 10.1016/j.proeng.2014.10.557

1. Introduction

Nigeria currently has a population that is put at over 140 million and this figure is on the increase at an annual growth rate of about 3.2% [1]. As a result, the country has a very large and ever-increasing housing deficit which stood at approximately 8 million housing units in 1991 and between 12 to 14 million housing units in 2007 [2]. The problem of housing deficit in Nigeria is as a result of rapid growth in population, skills shortages, high cost of building materials, logistical challenges etc.[3]. As a result of these problems, there is a wide gap between housing demand and housing supply in Nigeria [4-6]. There is work going on to reduce the current housing deficit in Nigeria but there is still so much work that needs to be done.

In the UK for instance, a good number of reports advocated for change within the built environment. Notable among these reports are the Latham report of 1994 (Constructing the Team) and the Egan report of 1998 (Rethinking Construction). As a result, there was a strong need for the construction industry to view construction as a manufacturing process [7]. This call for change is not peculiar with the UK only. In Nigeria, there have been suggestions that emphasis should be laid on other forms of construction such as prefab building [8]. Preliminary interviews with experts in the Nigerian construction industry showed that, in order to solve the problem of inadequate housing, there is the need for a shift from the conventional systems of construction to a more adaptable and faster way of construction. As such, 'Dry Construction' has been recommended by these experts [9, 10]. Dry Construction is described as a method of construction where majority of the components of the building are prefabricated off site and brought to site for assembling [10]. As identified by [Fussell, Blismas [11], Experian and SamiConsulting [12], Blismas, Wakefield [13], Azman, Ahamad [14]], there are opportunities for greater use of offsite manufacturing in the area of housing delivery. In countries like UK, USA, Japan, Scandinavian Counties, Australia, New Zealand, Malaysia etc., OSM has been adopted as a means of improving construction processes and also to improve housing delivery efforts [13, 15-19].

2. Problems of Housing in Nigeria

Housing (adequate shelter) is seen world-wide as one of the basic necessities of life and a pre-requisite to the survival of man. It is also important to the welfare, survival and health of individuals [5]. As opined by Olayiwola, Adeleye [20], housing remains one of the best indicators of a person's standard of living and his or her place in the society. In spite of the high importance given to housing, it is unfortunate that only 10% of Nigerians who desire houses can afford to acquire it either by purchase or personal construction, this is very low compared to 72% USA, 78% UK, 60% China, 54% Korea and 92% Singapore [1]. The problem of housing in Nigeria is caused by a number of factors [4, 21-24]. Among these problems are; rural-urban migration, high cost of building materials, inadequate regulatory and legal environment affect housing development, poor housing finance structures, skills shortage, limited diversity in construction processes and over reliance on cement [3, 25-27]. Some of the problems are highlighted below;

2.1. High Population Growth

Akinmoladun and Oluwoye [28] argued that the origin of housing inadequacy in Nigeria was as a result of high population growth rate experienced in the country which exceeds the rate of economic growth experienced in the country. This high population growth rate causes an increase in the demand for shelter and efficient supply and distribution of basic amenities and services for the city dwellers. In most urban centres in Nigeria, the problem of housing is not only restricted to quantity but also to the poor quality of available housing units [4]. There are strong indications that OSM has the capacity to deliver housing units at a faster speed and with higher quality compared to traditional construction [29-31]. For instance, in UK, aside from the fact that there was a move for change in the construction industry, OSM came into prominence after world wars 1 and 2 [32]. For OSM to be adopted in Nigeria, it is essential for barriers like lack of guidance and information, negative image etc. [16, 33] to be broken for Nigeria to fully enjoy the benefit of speed associated with OSM.

2.2. Skills Shortage

According to Chan and Dainty [34], the problem of skills shortage within the construction industry has been recurring over the past 30 years. This issue of skills shortage exists in almost all parts of the world to varying degrees, in the studies conducted by CIOB [35] and Schâfer [36], in UK and Germany respectively, it was identified that skills shortage existed in those countries. In the Nigerian context, Ayedun and Oluwatobi [1] identified skills shortage as one of the problems hampering the effective delivery of housing. One of the drivers to the uptake of OSM identified was skills shortage [29, 30, 37]. Since OSM takes away most of the construction processes to a controlled environment (factory), fewer operatives are needed because minimal work is done on site.

2.3. Unwillingness to Accept New Construction Practices

Ayedun and Oluwatobi [1] observed that the Nigerian Construction Industry as a whole was guilty of not accepting new technologies. This is also similar to the UK construction industry [38]. With the call for a shift from 'conventional' construction approaches to a more adaptable and faster way of construction [10], it is important for the Nigerian housing sector to put modalities in place for OSM to be incorporated into its structures. Adopting this method will not be easy, as there are several barriers associated with the uptake of OSM - as acknowledged in other countries where OSM is used [Fussell, Blismas [11], Goodier and Gibb [16], Arif, Bendi [29], Pan, Dainty [39], Jonsson and Rudberg [40], Rahman [41], Zhai, Reed [42]]. Housing delivery in developed and developing countries of the world are faced with many challenges. In the case of developing countries like Nigeria, the problems are multifarious compared to developed countries. The population of the world is increasing at an enormous rate and most of this increase is expected in developing countries [5, 43]. Acknowledging these statistics, it is important for developing countries to think of the way forward with regards to housing delivery.

3. Offsite Manufacturing and the Opportunity for its adoption in Nigeria

There are various terms and acronyms associated with OSM. They include OSM, manufactured construction, offsite construction (OSC), offsite production (OSP), pre-assembly, préfabrication, modern methods of construction (MMC) etc. and these terms are all used interchangeably [44-48]. For the purpose of this study, it will be referred to as OSM. Nadim and Goulding [38], argued that, offsite manufacturing falls under the broad umbrella of Modern Methods of Construction (MMC). Over the years, quite a number of definitions have been used to describe offsite manufacturing [46].

OSM can be defined as processes that incorporate préfabrication and pre-assembly to produce units and or modules that are then transported to site and positioned to form a permanent work [33, 37, 49, 50]. According to MBI [51], offsite manufacturing refers to any part or aspect of a construction process that is carried out in a controlled condition away from the actual site where the building is or will be situated. But Gibb and Pendlebury

[52], went a step further and defined OSM as a term used to describe a range of applications where structures, buildings or parts are manufactured and assembled away from the site before they are finally installed into positions. In a nutshell, offsite manufacturing involves moving operations that are traditionally completed onsite to a manufacturing environment [52] and this in turn improves the quality, customer satisfaction, efficiency, predictability of delivery timescale and sustainability of project [38].

Several benefits are obtainable from the use/adoption of OSM. These benefits have been categorized into sustainable benefits and process and objective based benefits. These benefits were highlighted in the works of [Arif, Bendi [29], Pan, Dainty [39], Arif and Egbu [44], Taylor [46], 53, Pasquire, Gibb [54], Jaillon and Poon [55], Boyd, Khalfan [56], Haas, O'Connor [57]]. The benefits of offsite manufacturing are highlighted in Figure 1. Gorgolewski

[53] identified the sustainable benefits of OSM, they are:

• Less Impact on the Surroundings

• Reduced Level ofDefect

• Less Waste in Manufacture

• Transportation

• Greater Efficiency in the use ofResources, Both Materials and Labour

Pitt, Tucker [58] ascertained that 40 per cent of all UK waste (including greenhouse gas emission) is produced by the construction industry. It has also been observed that most of these wastes generated from construction sites are deposited in landfills [53]. Also, it was observed that, about 13 per-cent of materials delivered to sites are never used and are therefore turned into waste [53]. In the case of Nigeria, as opined by Ajayi, Koleoso [59], a large volume of waste is generated in an average Nigerian site. It was found out that most wastes were generated from demolition works on site and material handling. To reduce waste generated on site, based on a research conducted by WRAP [60], it was observed that between 70 per-cent and 90 per-cent of waste reduction could be achieved with the use of OSM (depending on the particular OSM process being adopted). Also, it is easier to gather and recycle waste generated from OSM compared to traditional construction methods [60]. Additional benefits in support of this position can be seen in Figure 1.

BENEFITS OF OFFSITE MANUFACTURING

Reduced Onsite Occupational Health and Safety Risk. Reduced Environmental Impact During Construction Process

Process and Programme Improvement:

1. Speed of construction

2. Speed of commission

3. Reduced risk of delivery

4. Simplified construction process

Cost/Value/Productivity Improvement:

1. Reduced onsite cost

2. Reduced risks of cost overruns

3. Reduced onsite wastage, overheads and reworks

4. Reduced life cycle cost due to improved quality and durability_

Quality Improvement:

1. Factory controlled production and quality audit

2. Improved consistency of standards and quality

3. Reduced defects and snagging.

Improved Logistics and Site Operations:

1. Reduced site disruptions

2. Fast tracking: phrased preliminary onsite operation & factory production of components

3. Improved site layout and space by evading the need for raw material storage

4. Elimination of multi-trade interfaces especially in restricted work areas.

Fig. 1. Benefits ofOSM[ll]

3.1. Process and Programme Improvement

Gibb and Pendlebury [52] asserted that, "time is a big-plus for offsite". The time spent on site depends on the amount of factory produced components and those produced traditionally [32]. Construction time is normally affected by material shortage, skills shortage and bad weather conditions. In the case of OSM, these issues have been addressed because most of the building components are manufactured in factories and transported to site, this

drastically reduces the amount of time spent on site [32]. As a result of the short time spent on site, it is easier to predict completion dates and also access restricted site areas, for example airport closures and school holiday [52]. As identified by Taylor [32], the issues of material shortage and weather were also found to be similar to Nigeria [61], as argued by Taylor [32] to tackle these issues, the use of OSM can be adopted, this will help reduce the overall time spent on projects. In the works of [Arif, Bendi [29], Blismas and Wakefield [30], Lu [31], Gibb and Isack [37]], it was observed that one of the most important benefits of OSM was time, i.e. reduction in the time spent on site and faster pace ofdelivery ofprojects.

Building Construction at Plant

Fig. 2. Comparison between OSM Schedule and Site Built Construction Schedule [51]

Figure 2 identifies how time can be saved while using OSM as compared to site built construction. Based on the MBI [51] report, as a result of performing the site development and building construction at plant simultaneously, there is a 30 - 50 per-cent chance of finishing buildings faster. For professionals involved in construction especially project managers, having a method that improves quality of construction projects and reduces the overall time is indeed a great advantage.

3.2. Cost/Value and Productivity Improvement

OSM is believed to be more expensive than more established techniques (traditional method) NationalAuditOffice [62]. But Gibb and Pendlebury [52] argued that, savings from OSM can be achieved in the areas of cost certainty and reduced risk, less overall life cycle costs, better quality ofbuilding which will in-turn lead to reduced maintenance cost, reduced preliminaries and site overhead, reduced construction time which can result in cost benefit from early occupation of the property. According to WRAP [60], based on research conducted, it was observed that savings can be achieved by using OSM due to a reduction in waste of building materials especially bricks. In Nigeria were sandcrete blocks/bricks are generally used, incorporating OSM will go a long way in reducing waste on site.

3.3. Quality Improvement

As argued by the NationalAuditOffice [62], OSM meets the three quality requirements of durability, whole life cost and performance. In the works of [Fussell, Blismas [11], Arif, Bendi [29], Gibb and Isack [37]], based on researches conducted in India, Australia and UK respectively, it was realised that achieving greater quality was one of the major benefits of OSM and also one of the key drivers to its adoption in those countries. Quality can better be achieved within a factory and also, products consistency can be better achieved while working in a controlled

environment (factory) [37]. The problem of housing in Nigeria is not only in terms of quantity but also quality [20], as such adopting OSM will improve housing delivery efforts in terms of quantity and quality.

3.4. Improved Logistics and Site Operations

Reduction in wet trades, site disruptions and having more certainty over the control of projects, was found to be an important benefit of OSM [37]. A good example cited by Gibb and Isack [37] is, working in a prison, were contractors have to be escorted to and from their site and all employees have to be properly scrutinised, but if OSM is adopted, the amount spent on security will be reduced as less time will be spent on site by the contractor. Also in the case of airports, roads and rail projects, site access and working space are normally limited; as a result, OSM was seen to be of great benefit. OSM is a construction technique that has been adopted in a good number of countries for different reasons. In Nigeria, the current housing deficit demands that housing units need to be provided at a faster speed and from the experiences of other countries, OSM can deliver housing units faster and with superior quality compared to traditional construction.

4. Discussion

There are numerous factors hindering housing delivery in Nigeria [21]. One of the factors identified was high population growth [28]. As a result of rapid increase in population, there is pressure on the available housing stock. As stated by [Arif, Bendi [29], Lu [31], Gibb and Pendlebury [52]], time is a big plus for OSM, as such the use of OSM by the Nigerian housing sector will help increase the speed of housing delivery. There are indications that OSM can save the time spent on construction by about 30 - 50 per-cent compared to traditional construction technique [51]. OSM will go a long way in making housing delivery in Nigeria faster than it is currently.

Another problem of housing delivery in Nigeria as identified by Ayedun and Oluwatobi [1] was skills shortage. The current situation in Nigeria suggests that there is a shortage in manpower necessary for adequate delivery of the needed housing units. One of the drivers to the uptake of OSM in some developed countries was skills shortage [29, Blismas and Wakefield [30], Gibb and Isack [37]]. Since OSM requires fewer tradesmen [30], its adoption will eliminate the problem of skills shortage and as such, the possibility of meeting the demand for housing can be met with the few tradesmen available.

The issue of unwillingness to innovate is one that is associate with the construction industry all over the world, Ayedun and Oluwatobi [1] identified this problem with the Nigerian construction industry. OSM is a construction technique that is being used in a number of countries as various counties have found different reasons to adopt OSM into their construction processes. Based on the current situation in Nigeria, there are a good number of reasons to incorporate OSM, i.e. to improve housing delivery, to follow the trend that worked in developed countries etc. For OSM to be adopted in Nigeria, efforts need to be put by all the stakeholders involved in construction.

As much as there are many benefits associated with OSM, there are some barriers that have been found to hinder its uptake [Fussell, Blismas [11], Goodier and Gibb [16], Arif, Bendi [29], 39, Jonsson and Rudberg [40], Rahman [41], Zhai, Reed [42]]. Some barriers that have been found to hinder the uptake of OSM include; Negative Image, Reluctance to Innovate, Perception of Stakeholders, Perceived High Cost, Quality of Such Buildings etc.

Goodier and Gibb [16] identified negative image as one of the barriers to the uptake of OSM and for the Nigeria housing sector to adopt OSM, it will need to present a good image about OSM. Arif, Goulding [63] suggested that the OSM industry should focus more on visualization and simulation technologies as a means of creating awareness on OSM. When people see what is achievable using OSM, it is easier for it to be accepted.

The uptake of OSM is influenced by the perception of housing developers as to the advantage and disadvantage of OSM [39]. The issue of perception does not only lie on the developers, surveyors are also not familiar with OSM, as such, they do not really understand how to asses such properties [39]. Also, customers/clients are not really aware

of what OSM is all about and as a result, they are more inclined to the traditional method of construction, making it difficult for OSM to be adopted. For OSM to be adopted in Nigeria, it is important for the Nigerian housing sector to critically study and consult with experts who are into the use of OSM in developed countries.

5. Conclusion

With a housing deficit of about 17 million, it is necessary for housing units to be delivered at a faster pace to meet demand (to address this housing deficit). From the experiences of other countries, OSM has the potential of improving housing delivery in terms of speed, quantity and quality. In addition, it is recognised that OSM typically requires fewer trade-operatives compared to traditional method of construction. As such, the problem of skills shortages could be more readily managed with the adoption of OSM. Even though OSM has so many benefits, it is equally important to note that certain barriers are known to exist that can hinder its uptake in other countries. Some of these barriers include; negative image, perceived high cost, perception of stakeholders etc. For the Nigerian housing sector to incorporate OSM into its construction processes, it is important to learn from the experiences of these other countries that have already incorporated OSM into their construction processes. Government intervention through Research and Development could be one such way of improving housing delivery. Additionally, the use of Building Information Modelling (BIM) could be used to support OSM in overcoming some of OSM's weaknesses. Evidence to date has highlighted that OSM is still largely unknown in the Nigeria Construction industry. As such, additional work is needed to improve market penetration. Nigeria has the potential to leverage the collective experiences of other countries (in OSM) in a meaningful way in order to address its current housing delivery shortfall.

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