99 American Scientific Research Journal for Engineering, Technology, and Sciences (ASRJETS) ISSN (Print) 2313-4410, ISSN (Online) 2313-4402 © Global Society of Scientific Research and Researchers http://asrjetsjournal.org/ Socio-Economic Benefits of using Green Materials for the Construction of Low-Cost Buildings in Nigeria Shogo Musbau Adeniyi a* , Sarajul Fikri Mohamed b , Kolawole Olayinka Rasak c a,b Department of Quantity Surveying, Faculty of Built Environment and Surveying, Universiti Teknologi Malaysia, 81310 UTM Johor Bahru, Johor, Malaysia a Department of Quantity Surveying, School of Environmental Studies. Federal Polytechnic Offa, P.M.B 420. Offa. Kwara State, Nigeria c Department of Building Technology, School of Environmental Studies. Federal Polytechnic Offa, P.M.B 420. Offa. Kwara State, Nigeria b Email: sogo4qs@gmail.com , a Email: sarajul@utm.my c Email: rasakkolawole@yahoo.com Abstract It is explicit that earth and other green materials as been in use from time immemorial for construction of building at an affordable price before civilisation and adoption of conventional materials for construction works. However, in the resent era, the price of housing as increased to the extent that it is beyond the capacity of lower and middle class to construct or buy building of their own. Therefore, this paper is assessing the socio-economic benefits of using green materials for erection of structure at affordable prices. A quantitative method was adopted in carrying out this study using purposive sampling approach in data collection. Four hundred structured survey instruments circulated among the construction professionals in the north-central part of Nigeria, seeking their views on the benefits of using green materials towards provision of building at reasonable price. The responses received (76.20%), were analysed using analysis of moments (AMOS) via structural equation model (SEM). The results show that green material is cost-effective, readily available, energy efficiency, reduced cost of construction, reduced waste, improved the economy of the community promotes cultural heritage, adaptable to the environment, eco-friendly, enhance social wellbeing, and reduced carbon dioxide emission. Therefore, it is recommended that an integration of green materials will promote provision of more buildings to the citizenry at affordable rate. Keywords: Green materials; Affordable price; Socio-economic benefits; Purposive sampling; Structural equation model; Nigeria. ------------------------------------------------------------------------ * Corresponding author. American Scientific Research Journal for Engineering, Technology, and Sciences (ASRJETS) (2020) Volume 67, No 1, pp 99-108 100 1. Introduction The aspiration of people to build the house of their own or ability to own residential property is very high, but this remains a mirage due to the high cost of conventional materials. There are different versions of the definition of green materials by various scholars, and some defined it as sustainable environmentally friendly materials, while others feel that they are materials that are natural and subjects to reuse and recycle in building construction. Green materials are sustainable material, give high performance and save the precious environment [1], said as long as materials have a favorable effect on the environment that materials considered as green. Since building with conventional material at affordable rates becomes an issue in recent times, thus re- introducing green materials as alternative material will no doubt ease the flight of low-income earners in the country. Green materials are natural and recycled materials such as earth bricks, bamboo, recycled materials from waste, and others that are readily available within our environment. The socio-economic benefits of these materials assessed in this paper and the results of the Structural Equation Model (SEM) subsequently discussed. 1.1. Affordable building Building construction cost in the current century remained rocketed to the extent that it is now difficult for the low and middle-income earners to facilitate or construct the building of their own at an affordable rate; as a result of this there a lot of abundant or uncompleted buildings are within the community across the nation. The perception of building at a reasonable and economical cost is a challenging matter and remains a persistent and extensive difficult for several nations [2]. Internationally, accommodation affordability defines in many ways. The most common definition of affordable building refers to the housing affordability is taken as a measure of spending on construction or buying housing to income of the household [3]. Wikipedia defines affordable building as an element that can be afforded by that segment of people whose revenue is lower than the intermediate household revenue, the Us and Canada defined it as the ability of potential owner to have a building of his own at a cost not more than thirty per cent of his income annually [4,5], described an inexpensive building as a notion that is used to describe socio-economic and growth environs, that purpose of certifying if building to be developed for people can be achieved at an affordable cost by the target group of people within the low and middle-income earners. According to [6], there is major problem in the provision of adequate housing to the populace globally. It reveals that many people across all types of urban centers could not afford to have a building of their own or even afford the cost of paying rent [7], discovered that materials and construction methods adopted in accomplishing the building have a significant effect on the expensiveness and unaffordability of building to members of the society. In Malaysia, Reference [8] concluded in a study that notwithstanding the existence of inexpensive housing strategy for the State of Johor, housing cost remains at higher cost which makes difficult for majority of the people to achieve the aim of having personal house, and this reflected in the fact that the housing index for some of the area was harshly excessive amounts and mainly tricky for the people of the state to accommodate. 1.2. Green Building materials The building materials are one of the significant components in the construction industry that determines the American Scientific Research Journal for Engineering, Technology, and Sciences (ASRJETS) (2020) Volume 67, No 1, pp 99-108 101 overall total cost of constructing the building as it constitutes the most significant single input in executing a project [9]. Due to the escalated price of the conventional materials, stakeholders in the building industry now suggest alternative materials known as green materials to reduce the overall cost of construction[10,11,12,13]. Accordingly, potential green materials are materials that are locally oriented and renewable that are environmentally friendly; they composed of renewable rather than non-renewable resources [14]. It was further revealed by [14] that mixing of the natural materials into the construction of housing could mitigate the effect of the environment problem links with the production, conveyor, processing assembly, construction, recycle, reuse, and discarding of these materials. In a study, Reference [15] indicates the following as promising building materials for the construction of affordable housing:  Bamboo/Timber  Compressed earth bricks  Adobe blocks  Recycle materials  Improved concrete panel Figure 1: Various sizes of planks Figures 1, 2, and 3 show some of the available green materials in Nigeria. Bamboo are materials that are generally available in Nigeria, they are multi purposely use in construction of building at various stage of the building projects, in addition is it tension strength that has been established by materials expert to be more than that of mild steel[16,17]. According to [18] , bamboo is known to be one of the most fasted growth plants in the world and now considered as a replacement of steel and wood in construction activities. Timber is also a common material that is used for formwork, support, roof trusses, etc. in building construction process, it is American Scientific Research Journal for Engineering, Technology, and Sciences (ASRJETS) (2020) Volume 67, No 1, pp 99-108 102 available in various sizes and types (see figure1) at a reasonable price depending on the specification required[19,20,21]. Compressed earth brick is made from selected soil and has been the first building materials since the existence of humans. The technology of compressed earth bricks has, in recent times, increased and may be used to produce housing at affordable, durable, and robust [22]. According to[23], the materials for bricks are readily available, produced in mass, and required little or no maintenance with high durability and load-bearing capability. Figure 2: Earth brick column and the materials that used to made it. Figure 3: Thatches in stock with roof in place 1.3. Benefits of green materials The benefits of green materials are numerous and readily available in most of the countries across the globe. The American Scientific Research Journal for Engineering, Technology, and Sciences (ASRJETS) (2020) Volume 67, No 1, pp 99-108 103 introduction of green materials brings the cost of constructing a structure to the barest minimum and more cost- effectiveness as well makes accommodation affordable for more people in society [9]. Furthermore, Reference [24] reveals that rammed earth wall is 40% lower than the cost of a standard stud wall, including labour cost [24]. stressed that there are other benefits such as pleasant comforts and energy efficiency and unseen ecological benefit like enhance more oxygen to the environment [25], also postulates that green materials such as earth has a comparative environmental advantage over the building constructed of conventional material In the study carried out by [26], obtainability and affordability, among other advantages, are some of the significant benefits of using green material in building construction in Ghana [26]. Concludes that the flexibility and simplicity in technology of the usage of green materials promote the transfers of knowledge between the stakeholders in the building industry, individuals and communities at large can easily participate in the activities of constructing their building at an affordable cost. The summary of the previous study on the benefits of green materials presents (Table 1). Table 1: Previous study on the benefit of GMs No Author(s) Objectives of the study Benefits of Green Materials 1 Gohnert, Bulovic, & Bradley (2018) South Africa The need to develop low cost housing alternatives to make housing more affordable to people Green materials as an economical solution to the provision of building at affordable cost 2 Danso H. (2013) Ghana To examine and analyse the benefit and problem of houses constructed with local materials in developing country Promotion of cultural heritage, readily available, temperature regulation, affordable and cheap 3 Kumar, Gupta, Sagar, Singh, & Haroon, (2017) India To review the alternative construction materials and techniques for building design was established that fly ash brick, one of the green materials is comparatively low cost than the conventional bricks 4 Adegun & Adedeji, (2017) Nigeria To review the economic and environmental advantages and disadvantages of earthen materials for housing in Nigeria The earthen construction material discovered to have benefit of cost and cost to the environment. 5 Shen, Yang, Zhang, Shao, & Song, (2019) China Assessment of bamboo benefit and barrier for promoting bamboo as a green material in china The benefits of using bamboo summarised as; low cost, large scale and fast growth, lightweight and high strength, environmentally friendly, and socio benefit. 2. Methodology In carrying out this study, a purposive sampling was adopted, and survey questionnaire were distributed to Nigerian Building Construction professionals, such as; the Architects, Quantity surveyors, Building engineers, American Scientific Research Journal for Engineering, Technology, and Sciences (ASRJETS) (2020) Volume 67, No 1, pp 99-108 104 Civil engineers, and others that were recognised associates member of their respective organisation's body in Nigeria. Out of the four hundred survey forms dispersed in the north-central states of Nigeria, 95 were inappropriate responses either by incomplete filling or wrongly filled by respondents, therefore, make it unusable for the intended purpose. Thus, the 305 representing 76.20% questionnaires, which were suitable after the screening, were used for the data analyses. Table 2 shows the percentage distribution and the suitability of the responses accommodated in this research. Table 2: Total number and percentage of overall responses Sample Number of responses Percentage % Building Professionals 400 100.0 Unsuitable questionnaires 95 23.8 Suitable questionnaires 305 76.2 Overall response rate 76.20 2.1. Analysis and Result Discussion The structural equation model (SEM) used in carrying a confirmatory factor analysis (CFA) of the constructs. The construct, which was on socio-economic benefit (economic viability) of green materials, contains 15 indicators that evaluated in confirmatory factor analysis. The 15 observed variables derived from two sub-scales in part D of the survey (Figure 4), was the first measurement model for the concept of economic viability of green materials, and (Table 3) the displays for the first measurement model for economic viability of GMs construct. Figure 4: first measurement model (CFA) for construct on socio-economic benefit American Scientific Research Journal for Engineering, Technology, and Sciences (ASRJETS) (2020) Volume 67, No 1, pp 99-108 105 Table 3: Details of the first measurement model for concept on socio-economic benefit of GMs Construct Sub-construct Code Indicators Economic Viability of GMs Economic Benefits D1 Cost-effectiveness D2 Readily available D3 Energy efficiency D4 Create a job for people D5 Reduced cost of construction D6 Reduced waste D7 Aesthetics /beautification D8 Improved the economy of the community Socio- benefits D9 Promote cultural heritage D10 Improved occupant productivities D11 Adaptability to the environment D12 Eco-friendly D13 Improved social capital D14 Enhance social well being D15 Reduced CO2 emission The parameter of the suitability index (Figure3), specifies the unfitness of the initial measurement model, with indices results of ChiSq/df 2.331 less than 3.00, with AGFI, CFI, TLI and NFI all less than 0.90 except GFI of 0.916 which is greater than the specified 0.900, and (RMSEA=0.066 < 0.08). Thus, the model required adjustment by trimming the variables that less than 0.50 to accomplish a suitable index. The revised model for the construct on the socio-economic benefit of GMs, once low load items excluded, the final model (Figure 5) satisfied all the indices parameter for the acceptance of the results: P-value =0.041, RMSEA=0.046, GFI=0.977, AGFI=0.957, CFI=0.954, TLI=0.93, NFI=0.900 and ChiSq/df = 1.63. (Table 4) displays the indicators for the modified measurement model for concept on socio-economic benefit of green materials for affordable housing in Nigeria. Figure 5: Modified measurement model for construct on socio-economic benefits American Scientific Research Journal for Engineering, Technology, and Sciences (ASRJETS) (2020) Volume 67, No 1, pp 99-108 106 Table 4: Details for the modified model for construct on socio-economic benefits of GMs Construct Sub-construct Code Indicators Economic Viability of GMs Economic Benefits D1 Cost-effectiveness D2 Readily available D3 Energy efficiency D5 Reduced cost of construction D6 Reduced waste D8 Improved the economy of the community Socio-Benefits D10 Improved occupant productivities D11 Adaptability to the environment D12 Eco-friendly D14 Enhance social well being D15 Reduced CO2 emission The composite reliability and convergent validity for the model also realised with the CR value of 10.8, and 7.20 (≥0.6) and an AVE value of 1.80, and 1.44 (≥0.6). The overall fitness parameter accomplished. Table 5 displays information on the reliability and validity evaluation for the model. Table 5: Validity and reliability assessment for economic viability of GMs measurement model Constructs Sub-construct Items Factor Loading (≥ 0.5) AVE (≥ 0.6) CR (≥ 0.6) Economic Viability of GMs Economic Benefits D1 0.55 1.80 10.80 D2 0.55 D3 0.58 D4 deleted D5 0.51 D6 0.54 D7 deleted D8 0.56 Socio-benefits D9 deleted 1.44 7.20 D10 0.46 D11 0.51 D12 0.71 D13 Deleted D14 0.46 D15 0.55 3. Conclusion This study assessed the socio-economic benefits of using green materials for the realisation of affordable buildings for the average citizen of society. Analysis of moment structure (AMOS) a statistical software was used to carried out the structural equation modelling (SEM) on the useable data collected; the finding reveals American Scientific Research Journal for Engineering, Technology, and Sciences (ASRJETS) (2020) Volume 67, No 1, pp 99-108 107 that there are sound benefits of using green materials for construction of low-cost housing. The benefits include; cost-effectiveness, readily available energy efficiency, reduce waste, improve the economy of the community, improve occupants' productivity, adaptability to the environment, eco-friendly, enhance social wellbeing and reduce the emission of carbon dioxide. This outcomes of this study closely related to the results of [22, 9,25,27,28,29] on the advantages of using green materials. Thus, it is recommended that the adoption of green materials for construction works will promote the provision of more buildings at affordable prices in the developing country. 4. Acknowledgement Gratification goes to the Malaysia Ministry of Education (MOE) through the Research University Grant (RUG) funding number 1501, and the government of Nigeria that established Tertiary Education Trust Fund (TETFUND) for financial assistant while conducting this research project. References [1]. C. Fithian and A. Sheets, “Green Building Materials Determining the True Definition of Green Green [2]. 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