Mark Roose tudent Iden
A Report for
ubmitted in f Construct
epartment October 20 1
enbrand ntification N
n partial fu tion, Unitec
of Constru 15
ulfilment o c New Zeal
of the requ land.
or the Deg
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The construction industry is continually discovering ways to improve itself, whether it to reduce construction costs, increase productivity, minimise waste, become more sustainable or environmentally friendly and move towards becoming more lean. This research project investigates the effectiveness of scheduling methods in Aucklands construction industry and looks at the fundamental problem of construction scheduling and how this can differ from project to project. The research specifically looks at two main construction scheduling methods, Critical Path Method (CPM) and Location Based Scheduling (LBS) in Aucklands commercial construction industry to determine what is the most common scheduling method used and why, and also to determine what factors influence this decision.
Questionnaires and interviews are completed with a selection of people employed within Aucklands commercial construction industry, and their responses are analysed in order to answer the question above. It was found that CPM was the most common scheduling method in the Auckland commercial construction industry due to its ease of use, wide acceptance within the industry and its usefulness for justifying extensions to the project. Some of the factors which influenced the choice of scheduling method were the accuracy of the method, the software, the methods ease of use, company stipulations, and company and contractor knowledge. Client knowledge and stipulations were also considered. The research project has determined that the main factor which influences the scheduling decision is the industry norms, as CPM appears to be the only scheduling method used within the Auckland commercial construction industry.
It is recommended that the Auckland commercial construction industry increases its knowledge of linear scheduling methods by:
- Investigating the curriculum taught on construction courses to understand what is being taught to the new graduates in the industry.
- Adopting LBS for repetitive projects to gain efficiencies. Areas for future research are also recommended.
The author has agreed that all personal and company names of participants in this research will be kept confidential. Participants involved in the questionnaires and interviews are referred to by labels, for example Participant 1, Participant 2.
The author agrees that the Unitec Library and Department of Construction may make a hard copy or digital copy of this report available for the purposes of research or private study, provided that due acknowledgement is made where appropriate and that the authors permission is obtained before any material from the report is published.
I would like to take this opportunity to thank everyone that has supported me along the way in completing this research project. First I would like to thank those closest to me, my friends, family, work colleges, and partner for encouraging me through the process of completing this research project.
Thanks must also go out to my supervisor Dr. Linda Kestle who has continually provided me guidance and valuable feedback whenever needed.
This research project would not have been possible without the contribution from all the participants that kindly took the time to carry out the questionnaires and interviews and share their extensive knowledge and experience in the industry with me.
For everyone mentioned above I really appreciate your help and support over the last few months.
TABLE OF CONTENTS
Executive Summary ……………………………………………………………………………………….iii Confidentiality Statement ……………………………………………………………………………… iv Acknowledgements ………………………………………………………………………………………… v Table of Contents ………………………………………………………………………………………….. vi List of Figures ……………………………………………………………………………………………… vii Glossary ……………………………………………………………………………………………..viii
- 1 Introduction List of Abbreviations ……………………………………………………………………………………viii
- 1.1 Research Area and Question
- 1.2 Report Overview
- 2 Findings
- 2.1 Data Collection
- 2.2 Results
- 2.2.1 Demographics
- 2.2.2 Critical Path Method
- 2.2.3 Location Based Schedule
- 2.2.4 Success of scheduling method
- 2.2.5 Construction scheduling methods
- 2.2.6 Factors which influence the selection of scheduling methods
- 2.2.7 Interview outcomes
- 3 Discussion
- 3.1 Conflicting findings
- 3.2 Suitability of scheduling method
- 3.3 Factors influencing scheduling decisions
- 3.4 Willingness to adopt new scheduling methods
- 4 Conclusions and Recommendations
- 4.1 Conclusions
- 4.2 Recommendations
- 5 Reference list
- 6 Appendices
- Appendix A. Questionnaire
- Appendix B. Interview questions
- Appendix C. Questionnaire Key
- Appendix D. Questionnaire results
- Appendix E. Interview Matrix
- Figure 1: Role of participants in company LIST OF FIGURES
- Figure 2: Years of experience in their role
- Figure 3: Number of construction projects per year
- Figure 4: Company turnover
- Figure 5: Type of construction projects
- Figure 6: Familiarisation with CPM
- Figure 7: How often have you used CPM?
- Figure 8: Confident in using CPM?
- Figure 9: Familiarisation with LBS
- Figure 10: How often have you used LBS?
- Figure 11: Confident in using LBS?
- Figure 12: Influence of schedule on success of a project
- Figure 13: Comparison between CPM and LBS
- Figure 14: Involvement in determining the scheduling method
- Figure 15: Encouraged to consider different scheduling methods
- Figure 16: Who selects the scheduling method?
- Figure 17: Factors influencing the choice of scheduling method
Construction Scheduling This is a method of pre-planning undertaken by the main contractor, to enable them to plan out the activities required to complete a project against a time schedule. This can then be used as a tool to determine the labour, materials and costs required for a project.
Critical Path Method This method includes all work specified in the Contract Documents, including all activities required to complete the construction of the project. The critical path method is a visual representation of the project where the earliest start and earliest finish time for each activity is determined, and clearly identifies the critical activities necessary in order to complete the project within the allocated duration.
Location Based Scheduling This is a graphical planning method focusing on continuous resource utilization in repetitive activities. It provides a simple diagram to show the location and time at which a certain crew will be working on a particular activity.
LIST OF ABBREVIATIONS
2.2.2 Critical Path Method
2.2.3 Location Based Schedule
1.1 Research Area and Question
The construction industry is continually discovering new ways in which to improve itself, whether that is to reduce construction costs, increase productivity, minimize waste, become more sustainable or more environmentally friendly. This is known in the construction industry as becoming lean. The area of this research is an investigation into construction scheduling methods and their effectiveness in todays construction industry. It looks at the fundamental problem of construction scheduling and how this may differ from project to project. The construction schedule is a method of pre-planning, undertaken by the main contractor to enable the planning-out of activities required to complete a project against a time schedule. This can then be used as a tool to determine the labour and resources required for a project, where and when they are required, and the cost implications.
A literature review was previously carried out which categorised two main construction scheduling methods, Critical Path Method (CPM) and linear scheduling methods, all the literature reviewed examined the scheduling practises used around the world, however it identified there is very little investigation into the scheduling practises commonly used in New Zealand. This led to the development of the research question for this study which is: In the Auckland commercial construction industry, what is the most commonly used scheduling method and why, and what factors influence this decision?
The purpose of this research is to understand the most commonly used scheduling method in Auckland and why, and also to determine the reasoning behind the choice of scheduling method. The use of two different methods, CPM and LBS, in Aucklands commercial construction industry will be investigated. Due to the potential scale of the investigation, the limitation of one linear scheduling method, and one city have been applied to this research project.
There are two potential outcomes from this research project. The first is that Aucklands commercial construction industry uses mainly CPM, therefore there is great opportunity for large construction companies to become more lean by adopting linear methods. The second is that Aucklands construction industry is using linear methods, which will then allow Auckland to be used as a case study for other countries who are interested in exploring linear options.
1.2 Report Overview
This report begins with a section presenting the collated data from the questionnaire and semi-structured interview questions. The data analysis is also presented in this section including graphs, pie charts and the interview matrix table. This section contains factual information gathered from the participants only. A copy of the questionnaire, interview questions, questionnaire results and the interview matrix summarising the participants interviews can be found in the appendices.
This section is then followed by the discussions of the findings, and compares and contrasts the findings with the key themes from the previously completed literature review on this topic. In this section reasons for similarities and differences are suggested, with any unexpected results and significant findings highlighted.
The next section is the conclusion where the research question is answered completely, with suggestions for future research made, and the implication of the research results for the Auckland commercial construction industry stated. Recommendations are then made to the Auckland commercial construction industry and to research practitioners who are interested in developing and implementing lean construction practises.
2.1 Data Collection
The data collection process involved reaching out to invite a wide range of the large commercial construction companies in Auckland to participate in this research project. This was to ensure a wide spread of appropriate and targeted data would be collected. The research was carried out with nine participants from the Auckland commercial construction industry, across five construction companies. The gathering of data was conducted using questionnaires and semi-structured interviews.
The questionnaire comprised nominal questions to establish the general background of the participants such as their role in the company, their experience within the industry, and the size of their company. It also included ordinal questions in the form of the Likert scale to gather opinions of participants, such as their familiarity with the two scheduling methods, whether they agreed or disagreed with statements relating to the different scheduling methods and what roles within their company make decisions about scheduling methods. The aim of the questionnaire was to gather quantitative data in order to establish themes and trends between participants on the topic (Denscombe, 2010). The findings are presented in the following section. Refer to Appendix A for the questionnaire that each participant was presented and Appendix C and D for the results.
The semi-structured interview followed immediately after the questionnaire, this allowed the gathering of quality, opinionated data from the knowledge and experience of the participants. The semi-structured interviews used open-ended questions which allowed flexibility in the order of topics discussed and the participants were able to develop and relate their own opinions. The aim of the semi structured interview was to gather information from the participants and expand on their opinions provided in the questionnaire in order to gather quality data (Denscombe, 2010). Refer to Appendix B for the interview
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Figure 5: Type of construction projects
The participant companies are mostly involved in the construction of schools and hospitals, industrial warehouses and bespoke buildings, whereas high rise construction, infrastructure and large scale residential construction were less prevalent (Fig. 5). Again, this demonstrates the relevance of the data collected as the participants have been involved in a large variety of construction project types, as opposed to only one or two.
The general demographics detailed above clearly show that the information gathered is quality data due to the wide variety of participants with different roles and ranges of experience in large scale construction companies within the Auckland commercial construction industry.
Schools, hospitals Industrial Warehouses Bespoke buildings High rise construction Infrastructure Large scale residential developments
Type of construction projects
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2.2.5 Construction scheduling methods
Figure 13: Comparison between CPM and LBS
Figure 13 shows the participants opinions of the benefits of CPM and LBS. There was a clear belief amongst the participants that CPM helps reduce delays, results in time savings and increases the control over risk and uncertainty during a project. It was also found that participants believe CPM helps improve the understanding of a project and improves the pre-construction planning process. CPM is not believed to improve communication amongst the workforce. Participants generally answered neutral to all of the statements towards LBS apart from that it helps to minimise disputes on a project. This demonstrates that in general, CPM is believed to be more beneficial when used as the scheduling method on construction projects when compared to LBS.
Improves the estimating process Reduces delays Results in time savings Minimises disputes Increase control over risk and uncertainy Results in faster responses to problems Improves communication among the workforce Cost savings throughout the project Improves understanding of project Improves preconstruction planning
Comparison between CPM and LBS
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55% of participants are encouraged to consider different scheduling methods when they are selecting a scheduling method to use for a project, however the remaining 45% are either rarely or never encouraged to consider different scheduling methods (Fig 15). This demonstrates that within the Auckland commercial construction industry, some companies actively encourage their employees to consider different scheduling options for a project, rather than perhaps sticking to one or two preferred methods. On the other hand, a large percentage do not appear to encourage this at all.
Figure 16: Who selects the scheduling method?
Figure 16 shows that a range of personnel in the construction industry contribute to the selection of the scheduling method, with the exception of Commercial Managers who rarely play a role in the selection of scheduling methods. This demonstrates that many of the roles in the Auckland commercial construction industry are involved in choosing scheduling methods on construction projects, as opposed to one specific role.
Who selects the scheduling method?
Never Rarely Sometimes Often Always
2.2.6 Factors which influence the selection of scheduling methods
Figure 17: Factors influencing the choice of scheduling method
The main factors the participants often consider when choosing which scheduling method to use on a project are the accuracy of the method, stipulations from the company they work for, software, ease of use, and company and contractor knowledge of the method. Client knowledge and stipulations are sometimes considered, however the cost of scheduling programme never plays a factor in the decision making process (Fig. 17). This demonstrates that companies within Aucklands commercial construction industry are generally not concerned about the cost of a scheduling method, so long as it meets their other requirements, and are only influenced by the client sometimes in this decision making process.
Accuracy of method Software Company knowledge Contractor knowledge Ease of use Company stipulations Client knowledge Client stipulations Cost
Factors influencing the choice of scheduling method
Never Rarely Sometimes Often Always
2.2.7 Interview outcomes
The interview questions were designed to delve deeper into the most commonly used scheduling method used by each of the participants. From the responses to the questionnaires and interviews, it was found that for every participant, the most commonly used method was CPM, hence all the information gathered by the interviews and discussed below only relates to CPM.
188.8.131.52 Opinion of scheduling method used In general, CPM is the main scheduling method used within the Auckland commercial construction industry and the majority of people understand how to use this method. All the participants share the view that CPM is useful for explaining reasons for delays that occur on a project, and makes the process of obtaining an extension of time easier to negotiate. The majority of the participants made the comment that CPM is only as good as the data that is entered into the programme and needs to be frequently updated to be a useful tool.
184.108.40.206 Reasons for scheduling method success The participants believe that CPM is a successful scheduling method as it is easy to understand and read. They feel it allows the user to focus on the critical activities as well as small sections at a time, which makes it an effective tool for the user. They also believe that another main reason it is successful is the role it plays in justifying adjustments to the programme, as it visually demonstrates the factual information, which makes it easy to understand.
220.127.116.11 Challenges with scheduling method
All participants, except one, have experienced challenges in the past when using CPM. The participants found that they tend to focus too much on the critical path activities, and as a result lose focus on other activities which are not on the critical path, but are still very important, in some cases crucial to the construction process. Some of the participants experienced delays on a project as a result of this. Another challenge found with CPM is that it is a difficult tool to use to plan resources and productivity of workforce, and again can result in delays because of
this. In many cases estimates are used which are not accurate, the result being an inaccurate programme which doesnt progress as planned. The final challenge the participants have found with CPM is that often variations to the project are not updated in the programme, which results in the programme being inaccurate and therefore misleading. Each time a variation is authorised, the programme must be updated to remain tangible if it is to remain useful to the project.
18.104.22.168 Factors influencing scheduling method selection The majority of the participants stated that CPM is the standard scheduling method used within the Auckland commercial construction industry, and that there are no other scheduling methods being used currently, therefore this is the method that is always used. The participants also commented that the construction contract often states that CPM is the scheduling method to be used for a project.
22.214.171.124 Willingness to adopt a different scheduling method
All of the participants would be open to using a different method for construction scheduling, so long as they were provided with sufficient training to ensure they and everyone involved in the project, including the client, thoroughly understood the method. One participant commented that it is beneficial to know a range of scheduling method options, whereas another participant commented that they would rather not learn a new method, but would do so if required in their role.
3.1 Conflicting findings
One of the main themes identified in the findings, is that there are inconsistencies in some of the participants responses. The majority of participants stated that they were either slightly or moderately familiar with LBS, yet when asked about the perceived benefits of the method, the majority of participants answered neutrally. This raises the question as to whether they are actually familiar with the method, because if they were familiar with the method it is reasonable to expect they would have an opinion regarding the benefits of LBS instead of being neutral. Additionally, the interview questions identified that CPM is the norm in the Auckland commercial construction industry, and that other methods are not really used. This is conflicting with some of the questionnaire responses, where roughly one fifth of the participants responded that they sometimes or often use LBS as a scheduling method. Another common theme from the interviews was that CPM was used because the contract, which is client driven, requires this. The participants stated that the client understanding the method was therefore important to them, however during the questionnaire the participants stated that client knowledge and client stipulations were both only sometimes reasons for the selection of the method. This appears to be another inconsistency in the data collected.
There could be a number of reasons for these conflicting findings such as the participants not wanting to appear as if they did not know the method, as knowing how to schedule and programme projects is a big part of their role. Alternatively, their perceived level of understanding differed from the reality when faced with a discussion on the subject. To prevent this from happening in the future, instead of asking whether participants agree with statements it may be better to have them describe the method to show their understanding of it. Additionally, the research method could have contributed to these inconsistencies, as the participants may have rushed through the questionnaire as it is easy to complete, without actually thinking in depth about their responses
until they came to the interview questions. The format of the questionnaire and interview questions did not give the researcher the ability to probe the participants to understand the variance in their responses, and as such possibly gathering information via focus groups in future would allow for constructive discussions amongst the participants and the researcher. This would allow other participants to feed off each others thoughts and add valuable information and depth to the discussion, which would ultimately help in the gathering of more accurate and specific data (Denscombe, 2010).
3.2 Suitability of scheduling method
One of the main findings from the data collected was that CPM is the most common method used by all the participants. This is consistent with Ammar (2013) & Baweja (2006) who stated that this method is the most commonly used method in the construction industry. There was a strong knowledge of CPM amongst the participants, and their understanding of the method was in line with many of the authors stated advantages. It was found that the participants shared the opinion that CPM reduces the number of delays identified on a project, also results in time savings throughout a project, helps increase control over risk and uncertainty as well as helping to improve the understanding and preplanning of a project. The overall opinion of CPM was that it worked well for programming the sequence of works for a variety of projects and was an easy programme to use. Almost all participants mentioned that CPM was only as accurate as the information that was put into it and the frequency it is updated; therefore if little time was spent inputting the data or updating the programme it became impractical and irrelevant when applying the use in situations of dispute. This suggests that CPM is not always as suitable as the participants believe it to be if they are frequently finding the programme is out of date.
In general, the participants work on projects which are generally more suited to CPM, such as schools and hospitals, industrial warehouses, and bespoke buildings i.e. non-repetitive traditional projects (Ammar, 2013). That being said, sometimes
the participants work on high rise construction, infrastructure and large scale residential developments which Badukale & Sabihuddin (2014), Yamin, & Harmelink (2001), & Zhang et al. (2013) define as being repetitive projects. Several authors found that as a scheduling method, CPM is not necessarily the best method to use for repetitive construction projects and that the use of CPM is ineffective due to its inability to account for resource availability or work continuity (Badukale & Sabihuddin, 2014; Yamin, & Harmelink, 2001; Zhang et al., 2013).
All the participants were sometimes or quite frequently involved in selecting the method, and over half are sometimes or quite frequently encouraged to consider alternative scheduling methods, however CPM is always the chosen method as determined from the interviews. This is interesting as all the participants are involved in the selection of the method, and at least half are encouraged to consider alternative methods, yet they do not choose to use LBS which literature has found is more suited to some of the projects that they are involved in.
The participants also stated that some of the general reasons for the selection of CPM every time were because it is the industry norm, the industry isnt using anything else, and the contract calls for critical path. Another factor which could be influencing this trend is the participants knowledge of LBS. The majority of the participants are only somewhat familiar with LBS, therefore they may not completely understand the benefits of the method, and therefore do not choose this for their repetitive projects. These are possible reasons as to why no other methods appear to actually be considered, as it stands to reason that if they did consider LBS, it would occasionally be used by some of the participants, and that they would therefore have an opinion of the benefits of using this method.
3.3 Factors influencing scheduling decisions
The participants responses stated that the accuracy of the method was often one of the factors considered in the selection of the scheduling method, however Yamin & Harmelink (2001), and Yang & Ioannou (2004) found that when it comes to repetitive projects, the use of CPM is often inaccurate due to its inability to account for resource availability or work continuity. Another main finding in the literature was that the accuracy of the CPM schedule can be negatively affected by the lack of resources available in the industry and for the schedule to be successful the amount of resources required for the job must be known. Lu & Li (2003) found that CPM assumes unlimited availability of resources when using CPM which produces unrealistic schedules. The participants responses agree with the literature, such as when the participants stated that CPM didnt allow the ability to plan the productivity of the work force and it does not take into account the resource allocation and assumes maximum resources available. It therefore seems surprising when accuracy and resources were noted as being such an important factor to the project and the programme, that participants wouldnt seek to use a different method that may be better at allocating resources to the programme. One of the participants went so far as to state that controlling labour is more important than the programme, the programme only tells you how much labour you require and when you need it. Repetitive projects are sometimes carried out by the participants, however they only ever used CPM, therefore again it appears that perhaps they are unfamiliar or actually lack the knowledge in scheduling methods that are more suited for these types of projects such as LBS.
Zhang, Pan & Zou (2013) found that CPM is more commonly accepted by owners and construction contractors, even though it is not the most suited model because the use of CPM models are most often required as part of a construction contract. It seems as if this is true as a number of participants said that they use CPM due to most contracts calling for the method due to CPM having a critical path. This was
not asked specifically in the questionnaire and therefore would be an area to further investigate.
As discussed previously, a number of participants commented that CPM was the industry norm and that the industry wasnt using any other methods. This further raises the issue that there is an overall lack of knowledge in the different scheduling methods. This could stem from what methods are being taught at universities as Nageeb & Johnson (2007) found that at university level in the U.S., linear scheduling methods were not being taught but CPM was, and the reason for this was its what the industry is using. This could seriously influence the decision in which scheduling method to use when the only scheduling method being taught is CPM. This would result in a continuous cycle where universities are not teaching linear methods because the industry doesn’t use them, and the industry doesn’t use them because they don’t know about them. If this continued, then CPM would remain as the only method used in the construction industry, despite it being inefficient for certain projects. As such, this could be an interesting area for future research for the Auckland commercial construction industry, to determine if the findings in the U.S. are similar in Auckland.
3.4 Willingness to adopt new scheduling methods
The interviews found that the majority of the participants are open to using another scheduling method provided they were adequately trained in it, which is inconsistent with some of the literature findings where Nageeb & Johnson (2007) found that the reason LBS has not been widely adopted is due to the construction industrys resistance to change. This research project suggests the opposite of this, and that the Auckland commercial construction industry would be more than willing to adopt different methods, with one participant saying the more methods you understand, the more valuable you are as an employee. Also, as over half of the participants are encouraged to consider other scheduling options, this further demonstrates the
Auckland commercial construction industrys willingness to adopt alternative scheduling methods.
Furthermore, the most common theme found in regards to the adoption of a new model was the need to be trained in the method. The participants would only want to use the new method if they knew how to use it successfully. This is in line with Korman & Daniels (2003), and Baweja (2006), who suggested that in the construction industry there is a need to create standardised systems, and introduce training schemes in the use of scheduling due to a large number of poorly designed schedules by inexperienced users resulting in confusion, delayed projects and even ending up in lawsuits. It is therefore not only good practice to introduce training schemes but also critical to the success of the project that the employees are well trained and competent in using it. This could potentially be a reason that the majority of participants use CPM instead of LBS for projects which are more suited to LBS, as perhaps they have had a poor experience using LBS in the past due to lack of standards, and therefore do not have faith in the method.
Some participants expressed that if they inherited a critical path schedule from another employee it was often difficult to comprehend and understand the previous persons methodology. Galloway (2006) conducted a research study that found that CPM methodologies vary greatly in the industry and that there is no consistency or standards that are adhered to when CPM is being taught at university. It appears this could be true in Auckland as participants have expressed the difficulty in comprehending other Construction Managers programmes.
4 CONCLUSIONS AND RECOMMENDATIONS
As previously established, the participants involved in this research project are a good representation of the Auckland commercial construction industry as they have a wide variety of experience, roles, employers, and construction project exposure, therefore their comments and opinions can be used to draw conclusions about the Auckland commercial construction industry as a whole. From the study conducted, it is clear that the most common scheduling method used in the Auckland commercial construction industry is the Critical Path Method. The participants often select CPM as the scheduling method for their construction projects as they believe it to be a successful method which is easy to use for all parties, beneficial for the programming and sequencing of construction projects, and specifically helpful for justifying adjustments to the project schedule. There was a very good understanding of this method amongst the participants. This research study has also found that CPM is the only scheduling method used in the Auckland commercial construction industry, and this is another reason why the participants always opt for this method.
The main factors the participants stated which influence the scheduling method decision in the Auckland commercial construction industry are the accuracy of the scheduling method, the software, the methods ease of use, company stipulations, and company and contractor knowledge. Client knowledge and stipulations also play a part in this decision making process, however the cost of the method does not influence the decision of the scheduling method chosen. Although the participants did not state this explicitly, this research project has also concluded that there is a lack of knowledge in the Auckland commercial construction industry of alternative scheduling methods to CPM, and this is another factor which influences the selection of scheduling methods.
Most of the literature reviewed suggested that CPM is not the best method of scheduling when used for repetitive construction projects such as high-rise
construction or infrastructure. However, even though it appears that alternative methods are encouraged, the personnel involved in selecting which scheduling method to use always resort to using CPM, even on projects where LBS may be better. Specifically, the accuracy of the method was stated as an important factor for the decision of the scheduling method, however LBS methods have been proven to be more accurate when scheduling certain types of projects, hence the conclusion that there is a lack of knowledge within the Auckland commercial construction industry about this method.
This research project also concludes that the Auckland commercial construction industry would be willing to use alternative scheduling methods provided they were properly trained in the use of the programme, therefore the problem does not appear to be the industrys resistance to change as thought by previous literature. The final conclusion is with regards to the research method used. As demonstrated in the findings and discussion, there appears to be several areas in the research with conflicting opinions and statements from the participants. It is therefore concluded that a different data collection method, namely focus groups, could result in the depth of the information gathered from the participants increasing, and therefore providing more insights into the trends identified by this research project.
Based on the conclusions from the research project, it is recommended that the Auckland commercial construction industry increases its knowledge about alternative scheduling options available and the benefits of each. This will allow companies within the industry to make informed decisions about what method would best suit different projects, rather than just using the one that has always been used. This could ultimately result in projects being scheduled more accurately and therefore run more efficiently, to the allocated budget, and within the time constraints, thus contributing towards construction practices which are more lean and an industry which is more successful.
There appears to be a great opportunity for the Auckland commercial construction industry to adopt linear scheduling methods and apply these to certain construction projects, however this would not happen instantly and would need to involve re- training, upskilling, and construction companies taking the risk of using a new scheduling method for the first time. There are several recommendations for how this can be achieved.
The first recommendation is through further investigation into the current university curriculums, to understand if alternative methods to CPM are taught, and if so investigating the depth this subject is explored, and the practical application the students receive. This will assist in breaking the cycle of the industry not using different methods because it is not aware of alternative methods. Wider industry promotion of the alternatives via professional bodies, such as the New Zealand Institute of Building (NZIOB) and the New Zealand Institute of Quantity Surveyors (NZIQS) for example, will have a profound effect upon the knowledge base. Industry publications and general promotion to experienced client bodies will allow them to understand the options available to them and the potential benefits. This also allows Aucklands commercial construction industry to create and enforce standards to the alternative scheduling methods which will make them more successful over time.
The next recommendation would be for a construction company who are more regularly involved in repetitive construction projects taking the lead and running a project using LBS. They would have higher initial costs associated with using this method, as they would need to educate all the people involved in the project, however if the schedule is run correctly, the company could potentially benefit from improved accuracy and therefore eventual cost savings. Once they have proven that LBS is more accurate, the company will receive ongoing benefits if they continually use LBS for repetitive projects. This would also have a positive effect on the Auckland commercial construction industry as a whole, as other construction companies will observe the success of LBS and therefore be more willing to adopt this method, which will result in a shift in the whole industry towards considering alternative scheduling methods to CPM.
Areas of further investigation should include the number of commercial construction projects that are actually delayed in the Auckland commercial construction industry in order to quantify the problem of project delivery, and hence create a more compelling argument for adopting LBS. Another area for future research would be to continue investigating the topic of this research project within the Auckland commercial construction industry using a focus group research approach. As discussed, this will allow the researcher to probe further into the reasons for the trends identified in this project, and therefore further support the recommendations made, which would increase the likelihood of the Auckland commercial construction industry adopting the recommendations and therefore investing in LBS methods. At the least, it would further raise awareness of the alternatives.
If the recommendations above are implemented, this could contribute to the Auckland commercial construction industry becoming more lean.
5 REFERENCE LIST
Ammar, M. A. (2013). LOB and CPM integrated method for scheduling repetitive projects. Journal Of Construction Engineering & Management, 139(1), 44-50. doi:10.1061/(ASCE)CO.1943-7862.0000569
Badukale, P. A., & Sabihuddin, S. (2014). Line of Balance. International Journal Of Modern Engineering Research, 4(3) 45-47. http://dx.doi.org/10.6084/M9.FIGSHARE.1127921
Baweja, S. S. (2006). CPM schedules – Why and how. AACE International Transactions, 22.1-22.5.
Denscombe, M. (2010). The good research guide: For small-scale social research projects. (4th ed.). Retrieved from http://www.eblib.com
Galloway, P. D. (2006). Comparative study of university courses on Critical-Path Method scheduling. Journal Of Construction Engineering & Management, 132(7), 712-722. doi:10.1061/(ASCE)0733-9364(2006)132:7(712)
Galloway, P. D. (2006). Survey of the construction industry relative to the use of CPM scheduling for construction projects. Journal Of Construction Engineering & Management, 132(7), 697-711. doi:10.1061/(ASCE)0733-9364(2006)132:7(697)
Korman, R., & Daniels, S. H. (2003). Critics can’t find the logic in many of today’s CPM schedules users want software with flexibility, but is it true CPM? Engineering News Record, 250(20), 30-33.
Lu, M., & Li, H. (2003). Resource-Activity Critical-Path method for construction planning. Journal Of Construction Engineering & Management, 129(4), 412.
Nageeb, M., Johnson, B. (2007). Line of Balance scheduling: Software enabled use in the U.S. construction industry. Retrieved from http://ascpro.ascweb.org/chair/paper/CPRT157002009.pdf
Yamin, R. A., & Harmelink, D. J. (2001). Comparison of Linear Scheduling Model (LSM) and Critical Path Method (CPM). Journal Of Construction Engineering & Management, 127(5), 374.
Yang, I., & Ioannou, P. G. (2004). Scheduling system with focus on practical concerns in repetitive projects. Construction Management and Economics, (22)6, 619630. doi:10.1080/01446190310001649065
Zhang, L., Pan, C., & Zou, X. (2013). Criticality comparison between the Repetitive Scheduling Method and the network model. Journal Of Construction Engineering & Management, 139(10), -1. doi:10.1061/(ASCE)CO.1943-7862.0000736
Appendix A. Questionnaire
Appendix B. Interview questions
Q5 My company is involved in the following construction Never projects Rarely Sometimes Often Always
aHighb Schools, rise hospitals construction (^1234512345) c Industriald Infrastructure Warehouses (^1234512345) eLargefBespoke scale buildings residential developments (^1234512345) gOther (please specify) (^12345) Q6 a How Not familiar at all are you with Critical Path Method (CPM) for scheduling? familia 12345 r samiliaSlightlyr^ Somewhatfamiliar^ Moderatelyfamiliar^ Extremelyfamiliar^ bHow Never often have (^) Rarely you used CPM Sometimes as the scheduing Often method Always in construction projects? 12345 cI would Strongly be confident in using CPM as the scheduling method in a construction project. disagree 12345 Disagree Neutral Agree Strongly^ agree Q7 a How Not at familiar all are you with the Location Based Scheduling (LBS) method? familiar 12345 Slightlysamiliar^ Somewhatfamiliar^ Moderatelyfamiliar^ Extremelyfamiliar^ bHow Never often have (^) Rarely you used LBS Sometimes as the scheduing Often method Always in construction projects? 12345 cI would Strongly be confident in using LBS as the scheduling method in a construction project. disagree 12345 Disagree Neutral Agree Strongly^ agree Q8 In your opinion, how much of an effect does the scheduling method have on a project’s success? No effect Slight effect Somewhatan effect^ of^ Moderateeffect^ Strong effect
Appendix C. Questionnaire Key
Q1 What1Construction is your role Projectwithin your Manager company?
(^23) (^45) 6 Q2 How 10 many 5 years experience have you had in your role? 26311 (^10) 15 416521 (^2025) (^626) 7 30+ 30 Q3 On 10 average 5 how many construction projects does you company carry out per year? 26311 (^10) 15 416521 (^2025) (^626) 7 30+ 30 Q4 What 10 is 20 the million estimated annual turnover for your company? 221341 4060 millionmillion 4 60+ million ConstructionProject Manage Programmerr CommercialProject Director Manager Other (Please state)
Q9 For CPM state how much you agree or disagree with each statement below. Strongly
a disagree^123456 Disagree Neutral Agree Stronglyagree^ Dont^ know bc^123456123456
de (^123456123456) fg^123456123456 hi (^123456123456) j^123456 Q10 For LBS state how much you agree or disagree with each statement below. Strongly a disagree^123456 Disagree Neutral Agree Stronglyagree^ Dont^ know bc^123456123456 de (^123456123456) fg^123456123456 hi (^123456123456) j^123456 Q11 I am involved in determining the scheduling methods used by my company. Never Rarely Sometimes Often Always 1234 5 Q12 I am encouraged to consider a range of scheduling methods and choose the one that best suits the project. Never Rarely Sometimes Often Always 1234 5 Q13 Who usually decides which scheduling method to use within your company? Never Rarely Sometimes Often Always ab (^1234512345) cd (^1234512345) ef (^1234512345) g 12345 Q14 I determine the scheduling method used on projects based on: Never Rarely Sometimes Often Always ab (^1234512345) cd (^1234512345) ef (^1234512345) gh (^1234512345) i 12345 It results in faster responses to problems ItIt reducesimproves the the number estimating/bidding of delays on processthe project for projects ItIt (^) minimisesresults in time disputes savings between throughout contractor the project and client It increases control over risk and uncertainty It results in faster responses to problems ItIt resultsimproves in communicationcost savings throughout among the the workforce project ItIt improvesimproves (^) preeveryonesplanning understanding of the project of prior the projectto commencing work ItIt reducesimproves the the number estimating/bidding of delays on processthe project for projects ItIt (^) minimisesresults in time disputes savings between throughout contractor the project and client It increases control over risk and uncertainty CommercialProject Directo Manager r CompanyConstruction Directo Programmerr ItIt resultsimproves in communicationcost savings throughout among the the workforce project ItIt improvesimproves (^) preeveryonesplanning understanding of the project of prior the projectto commencing work ProjectContracts Manage Managerr EaseClient of stipulations use Company stipulations Other, please state CostAccuracy of method SoftwareCompany knowledge ContractorClient knowledge knowledge
Appendix D. Questionnaire results
QuestionQ1 111516323Participant 1 Participant 2 Participant 3 Participant 4 Participant 5 Participant 6 Participant 7 Participant 8 Participant 9 Q2 121276232Q3 544472752 Q4 434441431Q5 a323153533 Q5 b424553543Q5 c334453541 Q5 d133355531Q5 e333455411 Q5 f 423455533Q5 g N/A N/A N/A 5 N/A N/A N/A N/A N/A Q6 a555555544Q6 b545555545 Q6 c554555454Q7 a343135321 Q7 b312124121 Q7 c433135333Q8 455352454 Q9 a332242344Q9 b552241452 Q9 c554244454Q9 d543344353 Q9 e444345344Q9 f 453243333 Q9 g552252432Q9 h543232352 Q9 i 542354442Q9 j 5544N/A4454 Q10 a366333346Q10 b562334346 Q10 c563344336 Q10 d466334346Q10 e464334336 Q10 f463343336Q10 g562332336 Q10 h563332346Q10 i562325336 Q10 j564333346 Q11 443555445Q12 533123224 Q13 a343554414Q13 b441N/A54224 Q13 c221123213Q13 d444554415 Q13 e423124142Q13 f54N/A544224 Q13 gN/AN/AN/AN/AN/AN/AN/AN/AN/AQ14 a133121223 Q14 b443242433Q14 c144553223 Q14 d444554433Q14 e343554424 Q14 f334534334Q14 g344554413 Q14 h233554443Q14 i242554424
Appendix E. Interview Matrix
Q1- What is your opinion of the scheduling method you use?
Q2 - What makes the scheduling method successful and why?
Q3 - What challenges do you face with the scheduling method and have there been any negative experiences from the method. If so what were they?
What do you think are the most important factors your company considers when choosing the scheduling method?
Q5 If you started a project with a different scheduling method stipulated, what would be your opinion/reaction?
- Best method for their higher level of programming – Good in long term for project – Is the mainstream system used – Harder to prove EOT using LBS – Allows you to focus on critical activities
- Allows to plan at higher level and not get caught up in specific detail – Easy to prove acceleration and delays to the project – Easily understands the method
- Doesnt allow ability to plan the productivity of the work force – Can loose continuity throughout job and end up with guys not being busy on site – When focusing on the end date can loose focus on all activities leading up to it and only focus on critical path activities
- Company doesnt necessarily choose the method – CPM is the industry standard – Client calls for CPM in the contract
- Would want to be fully trained in the new method – Would be resistant at first – Feel more comfortable using CPM and push for that option first
- Most familiar method used and widely used due to the contract – When fully trained in the use of CPM can be a great tool however if unaware of how to use it, it can be unreliable
- Easy to read – Easy to use – You get out of it as much as you put in to it – Allows the possibility to focus on small areas without having to open up reams of the schedule
- In the early stages didnt have the training to use it therefore couldnt use it to its full potential (was difficult to use), It also allowed the entering of false data that didnt reflect the project to make the programme look right
- Felt that the industry isnt using anything else therefore the industry is dictating which method to use
- Wouldnt be opposed to it, however would expect training in the system to ensure understanding of how to use the method successfully.
- Likes CPM, feels it is effective in programming the project knows whats coming up and can plan for future works – must be constantly updated i.e. treated as a live document
- Depends on how much time and effort you put into the programme at the start need to think about reasonings and order of activities and enter accurate durations to get an accurate programme. – The more detail the more effective the programme
- Variations that occur can throw out the programme – When taking over the job from someone else can be difficult understanding their programme and methods expressed in the programme
- Use CPM as it is the industry norm – Use CPM as it is specified by the client so they can track progress – Company would allow the use of any programme so long as its understood by superiors
- Depends on method stipulated however would be open to the fact but training would be necessary – Could always use CPM as a side option if they felt stipulated method wasnt as good
- Works well with
- Focuses on critical
- If us
ed against for
- Doesnt consider any
- Wouldnt be adverse to
build sequence – Pretty basic – Depends on how logic is built into programme – Programme is only as good as the data input and the frequency it is updated – The critical path is not set in stone from the beginning
path items but can also be bad as too much focus on critical path, can lose focus on activities coming up
an EOT by the client they will go back to the original contract programme which hasnt included any variation works – Variations dont often get loaded into the programme – Not that flexible/easy to add changes to it.
other options – Use CPM as is the only method known and most widely used by all – Most contracts call for CPM
using different method, however definitely would require training in order to get the best out of it – who ever is reading the programme/using the programme would also need to understand it
Works well because the subcontractors and the client understands the method
- Provides a simple form of communication between the parties involved in the project
- Programme is affected due to current lack of resources available to meet the expected demands, i.e. it does not take into consideration resource allocation and therefore assumes maximum resources available
- The experience of the project team – Ensuring the teams understanding for the schedule
- Would require upskilling the staff involved in using the scheduling method and also the contractors that use/read the programmes.
- The more work on programmes the more jobs will finish on time and if they
- Man power must be calculated- must know how much labour is required
- CPM programmes that account for labour are much more difficult to use
- Choose the easiest one and the one that has always been used – Familiarity of the
- Would be fine as has used most methods in his career – Need to be aware of the software i.e. know the tricks
do finish late you will know why – The more input into the programme the better it becomes – The programme is only half the story resources available is the other half
- Realistic activity durations and sequences between activities – It lets you know when you need your labour and how much – Controlling labour is more important than the programme
and require a lot more computer skills – Need to be specialised in programming to gain accurate critical path which requires investment into the programme – CPM doesnt incorporate labour very easily i.e. difficult to incorporate so not normally entered.
programme – Often programmes are copied from previous projects and slightly adjusted
and how to overcome the frustrations of the programme and allow it to show what you want it to show. – Need to become familiar with the method – For disputes need to analyse the programme that was used and not change it because it then becomes messy and difficult to understand.
- Currently the only usable and practicable scheduling method they have used
- It calculated the minimum completion time for a project with possible start and finish times for the project activities. – Represents the sequence of work very well
- Doesnt face any challenges with the use of CPM method
- Usually dictated by the client. – Needs to meet the clients expectations – Needs to meet the clients reporting and understanding requirements
- Would be accepting of the method so long as it met the clients requirements
- CPM is easy to apply to a project – From a contractors point of view it
- Easy to read – Easy to alter and reschedule – Clear regarding any
- Procurement of materials can have factor on programme but doesnt always
- Requirement of client – Size of project
- Would assess the benefit of the current programme and assess the impact to all parties
makes disputes from the client regarding programme easy to resolve when delays have occurred.
delays and causes of delays
transfer to the critical path of the programme – Sequential activities will not show up on the critical path but all activities are critical
- After assessing would approach client about changing method
- CPM easy to use – Widely accepted throughout the industry – It generally captures all the requirements of the construction industry
- The programme is user friendly – A large pool of resources who can use it – Can get input from other parties and is easy to quickly update and show changes
- Monitoring and constantly updating the activities this sometimes relies on others as well – The programme is only as accurate as the person who enters and monitors the information in the programme
- Software available to use – The large number of people who are able to use it – That the programme is tried and true
- Participant would be open to using and trying a different method