International Journal of Technology Management and Information System eISSN: 2710-6268 [Vol. 2 No. 3 September 2020]
http://myjms.moe.gov.my/index.php/ijtmis
THE APPLICATION OF GREEN ROOF IN MALAYSIAN CONSTRUCTION INDUSTRY: ISSUES AND CHALLENGES
Mazura Mahdzir1*, Rozilah Talib2, Nik Norzahariah Ashikin N. Mohamed3, Sin Hui Qing4, Sharifah Mazlina Syed Khuzzan5 and Nik Fatma Arisya Nik Yahya6
1 2 3 4 Faculty of Built Environment, Tunku Abdul Rahman University College, Kuala Lumpur, MALAYSIA
5 Kulliyyah of Architecture and Environmental Design, International Islamic University Malaysia, Kuala Lumpur, MALAYSIA
6 Faculty of Engineering and Quantity Surveying, INTI International University, Bandar Bandar Nilai, MALAYSIA
*Corresponding author: [email protected] Article Information:
Article history:
Received date : 24 June 2020 Revised date : 9 July 2020 Accepted date : 10 August 2020 Published date : 1 September 2020 To cite this document:
Mahdzir, M., Talib, R., N. Mohamed, N., Qing, S., Syed Khuzzan, S., & Nik Yahya, N. (2020). THE APPLICATION OF GREEN ROOF IN MALAYSIAN CONSTRUCTION INDUSTRY:
ISSUES AND CHALLENGES.
International Journal Of Technology Management And Information System, 2(3), 9-23.
Abstract: The urbanization has affected the greenery in the Kuala Lumpur, and creating numerous environmental problems. To alleviate this, most of the countries have adopted the green roof system implementation as it could help to create a better environmental and reduce the negative urbanization effects. Malaysian has no exception to this as many commercial buildings have gradually implemented the green roof concept. However, it has not been widely accepted as Western Countries. If the concept and challenges of the green roof development in Malaysia cannot be identified and understand by construction industry players, the environment problems will continuously grow. Hence, this paper tries to tease out two objectives namely, (i) the challenges incorporated in green implementation and (ii) strategies to improve this situation in the urbanization area. To achieve this, a quantitative method will be used by distributing 150 set of questionnaire survey to the construction professionals via email (ie google form). However only 50 number of respondents responded to the questions. From the survey results, it was found that the main challenge of the green roof systems in Malaysia was due to the high cost of construction and maintenance of the green roof application. The respondents believed that this situation
1. Introduction
Natural landscapes helped to absorb and filter the storm water, cooling the excess heat, recycle the air and water quality, and offer habitats to creatures (Tam et al. 2011). However, due to the modernization era, many buildings have been developed and commercialised for the purpose of economic competition. This situation also known as the urbanisation process. This process might create pros and cons to the economic development. The good implications of having urbanisation is one’s countries might be in the competitive economically, whereas in a negative point of view, the urbanization process create many environmental problems to the natural landscapes, through building construction (Chow and Abu Bakar, 2016, Ismail et al. 2012).
Malaysia has no exception to this since rapid urbanization has created more artificial structure and reducing green space in Kuala Lumpur (Mohd Yusof, 2012). In other words, the urbanization has affected the greenery in the Kuala Lumpur, and creating numerous environmental problems (Ahmad et al. 2012). According to the study by Wei (2015), Kuala Lumpur may result in creating the worst Urban Heat Island (UHI) in future if not mitigated properly. Thus, the rapid urbanization in Malaysia could intensify the detrimental effects of global warming.
Realizing this situation, many countries have started to apply the green concept. For instance, Germany was the first country to investigate the use of green roofs for energy conservation (Hub, 2018). Other countries such as Japan and Singapore have made a big push for this idea in the last few years as it helped to create a better environmental and reduce the negative urbanization effects.
2. Literature Review
The term ‘green roof’ can be explained as a roof top garden with ornamental planting or fertile vegetation space (Grant et al. 2003), or known as a vegetated roof system that have been equipped with drainage to maintain the green space (Kristin et al. 2014).
Brownlie (1990) defined green roof as an area which ornamental planting with a substrate isolated from the natural ground by a man-made structure of at least one storey. It is also sometimes referred as eco roofs, living roofs or vegetated roofs (Ismail et al. 2008). The term eco roofs are occasionally used in connection with extensive green roofs (Grant, 2006).
could be improved if they received full support from the Government.
Keywords: green roof, environmental problems, sustainability, challenges.
It can be categorized into two types: intensive and extensive (Braithwaite, 2012; Chow and Abu Bakar, 2016). This notion was further elaborated by previous scholars, which mentioned that intensive green roofs also known as roof garden (Grant, 2006). This is because it can support small trees and shrubs. It is normally built on the roofs which is strong enough to support additional load (Chow and Abu Bakar, 2016).
Meanwhile, extensive green roof is more focused on the simple lightweight designs with hardy plants (Walbridge and Wills, 2016) or focus on plantings or vegetations. It is normally used to described as an energy efficient roof with photovoltaic cells or extra insulation (Grant, 2006). It will only cover by a thin layer of vegetation. The substrate layer of extensive green roofs is not more than 150mm which including vegetation (Chow and Abu Bakar, 2016).
Figure 1: Type of the Green Roofs (Myrthong, 2016)
In another point of view, Walbridge and Wills (2016) differentiate these two types of roof by stating that the green roofs Intensive green roof consists more complex plants, thus it is costly and difficult to develop compared to extensive green roof. Other types of green roof are semi-intensive which can be characterized by small herbaceous plants, ground covers, grasses and small shrubs which required moderate maintenance and occasional irrigation (Joe, 2019).
The functions of green roof concept are to sustains the building by using the natural of sun, wind and rain. It is made of a system of manufactured layers deliberately placed over roofing structures which support growing medium and vegetation. 50% of the rainwater can be retain through green roof system instead of rainwater discharge immediately in a convention roof. Green roof is a combination of plant, geotextile filter layer, drainage cell and water proofing membrane with their own specified function.
Due the functions possessed by green concept, most of the western countries have applied this construction either for residential or commercial projects. In fact, the implementation of this technology might give numerous benefits to the users such as in terms of improving the transmission of heat, air and sound reflection. Others, it was beneficial to the environment as the nature and habitats can be preserved and sustained.
Within Malaysian context, the green roof practice application in Malaysia were gradually implemented both for private and public projects. These include Ministry of Finance, Putrajaya, Serdang Hospital, Kl Sentral Park, Laman PKNS, Herriot-Watt University and Tun Razak Exchange. The adoption of this concept was identified in terms of mitigating the UHI and reduce the effect of greenhouse gases emission and global warming. Moreover, the application of green technology on roof elements would definitely practical as the roof area would represent around 21% - 26% of the total areas approximately in most urban areas (Kristin et al. 2014). Due to this, Ministry of Federal Territories and Urban Wellbeing initiated ‘The Greening of Greater KL’ and have targeted a total area of 150,000m2 of conventional roofs to be converted into green roofs by 2020. The sustainability element incorporated in the green roof application remains crucial because nowadays, our environment have been tremendously affected by rapid urbanization.
2.1 Problem Statement
Despite the green roof concept have been considered as an effective strategy to reduce the environmental problems in Malaysia, the number of building projects used this concept were considered low as compared to other Asian countries such as Singapore, Hong Kong and Japan.
(Ismail et al. 2012). If this scenario continues to happen, the environment problems will increase.
Thus, the objective of the paper is to identify the challenges in implementing green roof application in Malaysia and the strategies to reduce the challenges in the green roof implementation faced by the construction industry in Malaysia.
3. Method
The questionnaire survey will be used in this research to determine the challenges and the strategies to alleviate this situation in Malaysian construction industry. A total of 150 questionnaires were distributed to the developers, contractors and consultants via google forms. However, only 50 number of the respondents responded to the questions.
Table 1: Response Rates of Questionnaire Survey
Date Total sent Total Responded Response rate
Overall 150 50 87.5%
The questionnaires will be divided into four parts. The Section A will be used to identify the background of the respondent. The questions of the Section B will be set to identify the understanding of the respondents toward the concepts and benefits of the green roof. In Section C, the current situation and challenges in implementing green roof in Malaysia will be identified. In Section D involves the strategies to reduce the challenges in implementing green roofs in Malaysia.
Likert Scale Method will be used in part two, three and four. Likert Scale Method is always used as a part of a closed-ended question. It also can be defined as a survey scale which used to represent a set of answer that cover numerous opinions on a topic. Five-point scales are selected to be used in this study, which are: ‘1’ as strongly disagree, ‘2’ as disagree, ‘3’ as neutral, ‘4’as agree and ‘5’
as strongly agree.
3.1 Materials 3.1.1 Samples
The population for this research involves construction industry players that are very knowledgeable on the green roof application. Thus, the most appropriate type of sampling is purposive sampling. The selected respondents are coming from Quantity Surveyor with 20 number of respondents, Architect with a total of 12 respondents, Contractor with a total of 8 respondents, Engineer with a total of 7 respondents and the lowest number of respondents are from the Developers with 3 numbers.
3.1.2 Site
The sampling location will be carried out in Peninsular Malaysia specifically in Kuala Lumpur, Putrajaya, Selangor, Bangi and Shah Alam. The selection is made due to their rapid development in construction projects related to the green concept.
3.1.3 Procedures
The research is an exploratory basis and the analysis used is descriptive analysis. The variables in the study are the challenges in the green roof implementation (independent variables) and its strategies (independent variables) as well as the green building concepts (the dependent variables).
The sample of respondents are collected from developers, quantity surveyor, architects, engineers and contractors at the selected states namely Kuala Lumpur, Putrajaya, Selangor, Bangi and Shah Alam. The selection of the respondents remains appropriate and relevant as they have an experience, credibility and adequate knowledge in dealing with green buildings concepts. Hence, their suggestions to alleviate this issue will be recorded.
3.2 Data Analysis
The feedback collected from the respondents will be analysed using Statistical Package for Social Science (SPSS) version 16.0.
The data collected from questionnaire surveys are analysed using the Microsoft Excel and Statistical Package for Social Science (SPSS) version23 x 86 software to illustrate the statistics.
The data files are created, and the responses are entered as the variables. Whereas the statistical methods used are frequency statistics and descriptive statistics that displayed the analyzed results in the forms of table to show the percentage for necessary comparison between the variables.
The Likert scale method also has been applied for some questions, for example, to indicate the rate of agreement of the causes of abandoned housing project. The Likert scale as below:
5= Strongly agree, 4=Agree, 3=Neutral, 2=Disagree, 1=Strongly Disagree
Then, the ranking of challenges and strategies used to overcome this issue are calculated by finding out the mean values.
3.2.1 Validity and Reliability
The pilot test on the selected respondents were made. The main reasons for conducting a pilot case interview are as follow (i) to modify the contents (ii) to prepare the relevant questions and explanation for research design (Yin, 2009). This means that, the pilot interview was made to identify whether they faced any difficulties to understand the questions related to green concept.
These actions would help increase the accuracies (validity) and relevancy (reliability) of the data.
This was consistent with the works done by Thornhill, Saunders and Lewis (2009).
There are 5 group of respondents involved in the pilot case interview namely architects, engineers, quantity surveyors, developers and contractors., the pilot case interview was conducted. The session was done within one hour via semi-structured interview. Their viewpoint pertaining to the challenges and strategies to alleviate this issue are recorded. No modifications are required except restructuring the layout the questions to be more readable and understandable by others.
4. Results and Discussions
4.1 The challenges in implementing the green roof system
There are several challenges involved in implementing the green roof system implementation in Malaysia. The includes past failure of green roof, complicated and difficult to maintain, fear of unknown risk, susceptible to fire, lack of awareness on the green roof technology, limited local green roof expertise, limited local scientific research, lack of design standards and guidelines of green roof implementation for contractor and developer, high construction and maintenance cost, lack of incentives from government, high material supply cost (Ismail et al., 2012, Zhang et al., 2012, Li et al., 2014; Ezema et al. 2016; Williams et al., 2010; Braithwaite, 2012; Zahir et al.
2014). Further discussion was discussed as follow:
4.1.1 Past Failure of Green Roof
Table 2: Past Failure of Green Roof
Frequency Percent Valid Cumulative
Percent Percent
Valid Strongly disagree
26 52.0 52.0 52.0
Disagree 21 42.0 42.0 94.0
Neutral 3 6.0 6.0 100.0
Total 50 100.0 100.0
Table 2 represents the data collection based on the past failure of green roof as one of the challenges of the green roof system implementation faced by the construction industry in Malaysia.
It can be seen that 52% of the total respondents rated ‘strongly disagree’ and 42% of the total respondents rated ‘disagree’. They believed that this reason is not the main challenge that could influence the slow adoption of green roof. Whereas, there are 6% of the total respondents did not have any opinion on this challenge stated. There is no respondent agreed that this factor is one of the challenges of the green roof system implementation faced by the construction industry in Malaysia.
4.1.2 Complicated and Difficult to Maintain
Table 3: Complicated and Difficult to Maintain
Frequency Percent Valid Cumulative
Percent Percent
Valid Strongly disagree 8 16.0 16.0 16.0
Disagree 17 34.0 34.0 50.0
Neutral 14 28.0 28.0 78.0
Agree 11 22.0 22.0 100.0
Total 50 100.0 100.0
Table 3 discusses about the difficulties to maintain during pre, post and during the maintenance period (Weiler and Scholz-Barth, 2009). Moreover, different type of green roof required different maintenance standard. In essence, the maintenance cost for the green roof are more difficult as compared to traditional roof because less green roof specialist in Malaysia and more maintenance requirement needed (Weiler and Scholz-Barth, 2009). However, not all of them agreed with this notion as the highest frequency achieved was ‘disagree’ which consist of 17 respondents. 22% of the total respondents rated ‘agree’ and 28% of the total respondents rated ‘neutral’ for this challenge. Lastly, 16% of the total respondent rated ‘strongly disagree’ on this challenge.
4.1.3 Fear of Unknown Risk
Table 4: Fear of Unknown Risk
Frequency Percent Valid Cumulative
Percent Percent
Valid Strongly disagree 4 8.0 8.0 8.0
Disagree 10 20.0 20.0 28.0
Neutral 8 16.0 16.0 44.0
Agree 19 38.0 38.0 82.0
Strongly agree 9 18.0 18.0 100.0
Total 50 100.0 100.0
Table 4 shows the challenges in terms of fear of unknown risk. The unknown risk was contributed by many reasons namely temperature, weather, experiences, available plants and substrates (Ismail et al.,2012). Chow and Abu Bakar (2016) added that the increased in the unknown risk of the green roof implementation may cause by the less green roof specialist in Malaysia. This notion was agreed by 38% of the total respondents (rated ‘agree’) and 18% of the total respondents (rated
‘strongly agree’). The remaining of them would not agree as only 8% of the total respondents rated
‘strongly disagree’ and 20% of the total respondents rated ‘disagree’. Whereas, about 16% of the total respondents did not have any opinion on this challenge.
4.1.4 Susceptible to Fire
Table 5: Susceptible to Fire
Frequency Percent Valid Cumulative
Percent Percent
Valid
Strongly Disagree
27 54.0 54.0 54.0
Disagree 8 16.0 16.0 70.0
Neutral 4 8.0 8.0 78.0
Agree 11 22.0 22.0 100.0
Total 50 100.0 100.0 0.00
Table 5 discusses the characteristics of green roof, that is susceptible to fire. Basically, the construction of green roof is more likely to prevent the fire from occur. This is because the green roof is used for plantation and the plantation contains high level of water content which prevent the fire from happening. Knowing this advantage, most of the respondents disagree that the slow adoption of green roof concept was due to this challenge. This was proven when the highest frequency achieved was by ‘strongly disagree’ which consists of 27 respondents. 16% of the total respondent rated ‘strongly disagree’ on this challenge. Meanwhile, 8% of the total respondents rated ‘neutral’ and 22% of the total respondents agreed that susceptible to fire is one of the challenges of the green roof system implementation faced by the construction industry in Malaysia.
4.1.5 Lack of Awareness on the Green Roof Technology
Table 6: Lack of Awareness On The Green Roof Technology
Frequency Percent Valid Cumulative
Percent Percent
Valid Disagree 26.0 26.0 26.0
Neutral 6 12.0 12.0 38.0
Agree 18 36.0 36.0 74.0
Strongly disagree 13 26.0 26.0 100.0
Total 50 100.0 100.0
According to the table 6, the lack of awareness of public and private organisations on the green roof technology has been claimed as one of the challenges in the green roof implementation. (Chow and Abu Bakar, 2016; Tong, 2018). This was acknowledged by majority of the respondents as 26% of the total respondents are strongly agree and 36% of total respondents agree with this notion.
Meanwhile, 12% of the total respondents rated as neutral and 26% of the total respondents are disagreed with this statement.
4.1.6 Limited Local Green Roof Expertise
Table 7: Limited Local Green Roof Expertise
Frequency Percent Valid Cumulative
Percent Percent
Valid Neutral 7 14.0 14.0 14.0
Agree 22 44.0 44.0 58.0
Strongly
21 42.0 42.0 100.0
Agree
Total 50 100.0 100.0
According to the table 7, it shows that adoption of green concept remains low due to the limited local expertise on green roof technology. As a result, majority of the respondents agreed this notion has become one of the challenges in implementing the green roof system, with 44% and 42% of the total respondents rated ‘agree’, and ‘strongly agree’. Only 14% of the respondents holding
‘neutral’ opinion with this challenge. Lastly, there are no respondent disagree with such a statement.
4.1.7 Limited Local Scientific Research
Table 8: Limited Local Scientific Research
Frequency Percent Valid Cumulative
Percent Percent Valid Strongly Disagree
8 16.0 16.0 16.0
Disagree 11 22.0 22.0 38.0
Neutral 12 24.0 24.0 62.0
Agree 14 28.0 28.0 90.0
Strongly
5 10.0 10.0 100.0
Agree
Total 50 100.0 100.0
Table 8 clearly indicates that 28% of the total respondents rated ‘agree’ and 10% of the total respondents rated ‘strongly agree’. This is consistent with the Ismail et al., (2012), which stated that the lack of scientific research in green roof technology may resulted in inappropriate vegetation and substrates selection. It will indirectly increase the maintenance cost of the green roof implementation. Whereas, the remaining respondents were disagreeing with this factor by rating ‘disagree; at 22% and ‘strongly disagree’ at 16%. In the meantime, the opinion of ‘neutral’
are made up of 24% of the total respondents.
4.1.8 Lack of Design Standards and Guidelines of Green Roof Implementation for Contractor and Developer
Table 9: Lack of Design Standards and Guidelines of Green Roof Implementation for Contractor and Developer
Frequency Percent Valid Cumulative
Percent Percent
Valid Disagree 17 34.0 34.0 34.0
Neutral 16 32.0 32.0 66.0
Agree 14 28.0 28.0 94.0
Strongly
3 6.0 6.0 100.0
Agree
Total 50 100.0 100.0
Table 9 discusses about one of the challenges of the green roof system implementation in terms of having the lack of design standards and guidelines for the contractor and developer. (Chow and Abu Bakar, 2016 and Ismail et al., 2008). From their point of view, there is no a proper and standardized way to control the process of the green roof implementation in Malaysia. This was stressed by part of the respondents with 28% of the total respondents rated ‘agree’ and 6% of the total respondents rated ‘strongly agree’. Another 17 of them disagree with this notion and 32% of the total respondents rated ‘neutral’ for this challenge.
4.1.9 High Construction and Maintenance Cost
Table 10: High Construction and Maintenance Cost
Frequency Percent Valid Cumulative
Percent Percent
Valid Neutral 4 8.0 8.0 8.0
Agree 26 52.0 52.0 60.0
Strongly
20 40.0 40.0 100.0
Disagree
Total 50 100.0 100.0
It can be seen from the table 10 that high construction and maintenance cost of green roof system implementation has become the most significant challenge faced by the construction industry in Malaysia. 52% of the total respondents are agree and 40% of total respondents are strongly agree with this statement. In fact, this factor also was experienced by other countries such as Singapore (Wong et al. 2003). Besides that, only 8% of the total respondents rated as neutral and no respondent disagreed with this statement.
4.1.10 Lack of Incentives From Government
Table 11: Lack of Incentive From Government
Frequency Percent Valid Cumulative
Percent Percent
Valid Disagree 11 22.0 22.0 22.0
Neutral 9 18.0 18.0 40.0
Agree 14 28.0 28.0 68.0
Strongly
16 32.0 32.0 100.0
Disagree
Total 50 100.0 100.0
According to the table 11, about 28% of the total respondents rated ‘agree’ with the notion that the incentives provided by government could help in reducing the burden of high cost bear by the green roof developers. (Ismail et al., 2012; Ezema et al., 2016; Zhang et al., 2012). However, another 32% of the total respondents rated ‘strongly disagree’ and 22% of the total respondents rated ‘disagree’ with this statement. Lastly, 18% of the total respondents did not have any opinion on this challenge stated.
4.1.11 High Material Supply Cost
Table 12: High Material Supply Cost
Cumulative Frequency Percent Valid Percent Percent
Valid Disagree 10 20.0 20.0 20.0
Neutral 12 24.0 24.0 44.0
Agree 17 34.0 34.0 78.0
Strongly disagree 11 22.0 22.0 100.0
Total 50 100.0 100.0
According to the table 12, majority of the respondents agreed that high material supply cost is the biggest challenge in implementing the green roof system in Malaysia, which 34% of the total respondents rated ‘agree’, and ‘strongly agree’ made up of 22% of the total respondents that high cost of the material supply in Malaysia is caused by limited green roof supplier (Ismail et al., 2012). Meanwhile, 24% of the respondents holding ‘neutral’ and 20% of the total respondents disagree with this notion.
4.2 Strategies to Reduce the Challenges in Green Roof Implementation
From the table 13, there are 6 strategies to alleviate this situation. Firstly, was through initiatives of the government, as they should provide incentives for the owner or developer (mean 3.84). It followed by increasing public awareness on the green roof technology with the mean 3.70.
Providing a standard guideline for developer and contractor was ranked 3 with a mean 3.54, which is just less 0.16 from the rank 2. Three of these solutions having a higher mean as compared with other solutions suggested. Then, a certain percentage of green space on the roof is required and compulsory for the project development, with rank number 4 with the mean 3.12. The green roof system as a statutory requirement with condition has become the rank 5 with the mean 2.28. Lastly, more green roof system inspection to be carried out and studied is on the rank number 6 with the mean 2.26, which just less 0002 with rank 5. By having a lower mean, this means that most of the respondents agreed that both of these solutions were quite least significant.
Table 13: Descriptive Statistics on the Solution to Reduce Challenges of Green Roof System Implementation
N Std.
Valid Missing Deviation Min Max
Mean Rank
Standard
50 0 3.54 1.265 1 5
guidelines 3
Increase the
Public 50 0 3.70 1.093 2 5
awareness 2
Government
provides 50 0 3.84 1.131 2 5
incentives 1
Statutory
50 0 2.28 1.144 1 4
requirement 5
Green roof is
50 0 3.12 1.003 2 5
compulsory 4
More green Roof
50 0 2.26 1.006 1 4
inspection to
be studied 6
5. Conclusion
This paper has explored the challenges faced by the construction industry in Malaysia. The main challenges were the high construction and maintenance cost of the green roof system. The capital and maintenance costs were definitely to be higher than a conventional roof. This was followed by limited local expertise, lack of incentive from the government, lack of awareness on the green roof technology, high material supply cost, fear of unknow risk, lack of design standard and guidelines of green roof system to the Developer, lack of local scientific research, complicated and difficult to maintain, susceptible to fire and past failure of green roofs. The results also shown that effective way to improve this situation is through government involvement as they have the money and able to assist the developers financially. Thus, the main support from the Government is needed to ensure the implementation of green roof in Malaysia succeed.
6. Acknowledgement
The authors are grateful to the Department of Quantity Surveying from Faculty of Built Environment (FOBE) TARUC Main Campus for providing the opportunities to carry out this research area. The authors also appreciate any constructive comments from reviewers and solely responsible for any mistakes from this manuscript.
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