Critical Success Factors for Implementing Building Information Modeling (BIM) in Construction Industry

Succar [3] defined BIM as “a set of interacting policies, processes and technologies generating a methodology to manage the essential building design and project data in digital format throughout the building’s life-cycle”. BIM has developed civil engineering industries and construction process over the last years [4]. The implementation of BIM has been slowed particularly in small firms [5,6]. Many solutions have either concentrated onto technical issues (for example, software interoperability and software and training costs) or non-technical issues (for example, cultural change and legal uncertainties) [4,7]. However, solving these issues needs a better knowledge about Critical Success Factors (CSFs) to implement BIM successfully [8]. Rockart [9] defined CSFs as: “few key areas of activity where favorable results are absolutely necessary for a manager to reach his/ her goals.” Therefore, CSFs for BIM implementation was defined by Won [10] as a group of key areas that motivate stakeholders to alter their traditional project delivery system to implement BIM collaboratively from the beginning of design phase to facility management phase.


Introduction
Similar to other industries, the construction firms took advantageous from information and communication technology (ICT) application [1]. With respect to productivity and effectiveness, Building Information Modeling (BIM) offers advantages for implementation, design, scheduling, and facility management [2].
Succar [3] defined BIM as "a set of interacting policies, processes and technologies generating a methodology to manage the essential building design and project data in digital format throughout the building's life-cycle". BIM has developed civil engineering industries and construction process over the last years [4]. The implementation of BIM has been slowed particularly in small firms [5,6]. Many solutions have either concentrated onto technical issues (for example, software interoperability and software and training costs) or non-technical issues (for example, cultural change and legal uncertainties) [4,7]. However, solving these issues needs a better knowledge about Critical Success Factors (CSFs) to implement BIM successfully [8].
Rockart [9] defined CSFs as: "few key areas of activity where favorable results are absolutely necessary for a manager to reach his/ her goals." Therefore, CSFs for BIM implementation was defined by Won [10] as a group of key areas that motivate stakeholders to alter their traditional project delivery system to implement BIM collaboratively from the beginning of design phase to facility management phase.
BIM usage is various at all stages of the construction project lifecycle: owner used it to comprehend project requirements. Design team used BIM to design, analyze, and develop project. Contractor used it to manage the project and facility manager used it during operation phases [11]. Management teams may use BIM to collaborate, visualize and manage construction work better [4,12,13].
BIM technology offers a range of direct and indirect benefits and has made the whole design and construction procedure more simplified and obvious in many sides [14]. It is not unnoticed by 002 Civil Engineering Research Journal experts in construction industry that the BIM implementation may reduce re-work, waste, delay and reduce overall cost to name a few [15]. Azhar [4] reported that BIM can reduce unbudgeted change by 40%, and reduce the project time of completion by 7%, and the time to make a cost estimate by 80%. Eastman [6] in another project stated that BIM as a result of earlier clash detection saved 3-5% of whole project cost and 2-4% of overall time. As the primary principle of integrated project delivery (IPD) to integrate systems, parties, and business structures and improve collaborative process, BIM also used to integrate design and construction and encourages more collaboration and communication between all stakeholders to improve efficiency, reduce costs and waste through all phases of the project life cycle [6,13,[16][17][18][19].

Literature Review
BIM is able to do effective and fast decision-making, this done through instantaneous processes [20]. Azhar [4] suggested that building information model helps to choose the best position of the construction on the site. BIM also can reduce risk distributed with the same contract like claims or litigation [8,[21][22][23]. Eastman [6] reported that building information model formed at the design stage must be linked with construction plan and other scheduling tools. These coordination and planning activities assist project team to manage construction implementation more effectively and efficiently and forecast possible error and opportunities for substantial improvement [6,20]. BIM could give more predictable environmental data (for example, predict airflow and weather) and it may contribute to establish a model of good practice for BIM and sustainability implementation [24,25].
Comprehensiveness of predictable data improve the lifecycle data management [26,27]. On the other hand, sustainable solution may lead to reducing carbon emissions and improve sustainable building design, construction and operation [4,6,13,22,28]. By using BIM, building proposals can be effectively analyzed, quickly simulated, and assisting better-quality and innovative solutions, this help to improve construction project performance quality and increase productivity [3,4,20,22,23,[29][30][31][32][33]. The digital BIM model gives data for energy analyses and estimations of the consumption of energy may be determined [14,22,34]. The model can be determined lower energy consumption as well as determine where corrections are needed [21,24]. Azhar [21] and Eastman [6] asserted that an assessment of energy analyses throughout the design stage consider as a CSF for a BIM successful implementation.
Also, most of proposals are better understood by the non-technical people such as clients through accurate visualization and prefabrication of materials because they able to see end product off-site; so, client's request for BIM maybe increase [4,8]. The traditional method of documentation was used paper [35]. When BIM came up, it transferred the paper-based methods and placed them on a computer-generated environment, as a result of that BIM supply a high level of efficiency, management, and integrating of project documentation of the site [3,6,22,35]. Matarneh & Hamed [30] and Bryde [18] concluded that the ability of BIM to reducing the time needed for documentation process in construction projects and produce flexible documentation output. With BIM-based practices, organizations may get a greater Return on Investment (ROI) by means of a better design process which rise the value of project data in each phase and reduce the requirement to produce this data [8,36]. Selecting BIM services that meet investment goals of an organization are important for increasing ROI through BIM adoption [10].
Visualization of design allows building components to be built and viewed in a simulated environment and combine all these components inside BIM model (i.e. combining structural, architectural, mechanical, plumbing and electrical models) [22]. Also, Sun [37], Azhar [4] and Manning & Messner [36] stated that 3D visualization can be easily and quickly generated in a building and it helps project professionals to do more accurate development. 4D modelling allows stakeholders to visualize construction sequencing, fabrication and planning of suggested construction methods as well as, identify and reduce problems related to off-site construction by providing offsite prefabrication models [4,6,8,28,[37][38][39]. So, visualization is one of the CSFs of BIM implementation [34,[40][41][42].
In construction document phase most companies used BIM to make a design code checking to check construction projects [4,6,22,43]. BIM also is used for 3D or 4D clash discoveries [44]. BIM make physical and functional features of a construction and give a chance to correct design errors and implement any changes before a building is actually established and this is consider as a CSF for implementing BIM [4,18,30,37].
Antwi Afari [22] and Bansal [45] conduct that physical and geographical characteristic of any facility is reliant on three main things: early construction site works, layout of temporary site facilities, and construction site safety planning. Senior manager in the organization is responsible for safety in general and the ability of safety trainers to improve the quality of training meetings [46]. The results of senior manager responsibilities to site safety training are little injury occurrences and assist to develop a company's safety culture [47]. Zhang [48] stated that BIM is used to recommend a rule-checking safety system which particularly use for fall protection like guardrails. Thus, BIM simplifies scheduling, 3D modelling, and joining them together to visualize safe construction activities.
BIM make production of shop drawings of the building and assembly of structural systems more quickly and easily than traditional methods [4,[6][7][8]37]. BIM also is used by facility management department effectively by using the all information in the model for maintenance operations and managing the building over project time [4,8,20,37]. Anticipating benefits from the use of BIM is reduced transaction costs . BIM potentially used to transaction and overall cost via modification of specifications, drawings, and bills of quantities [36]. In this context many Software companies build BIM software in cost estimation characteristics, Civil Engineering Research Journal material quantities are also automatically extracted and can updated when designer do any change in the model [4,37]. Some of extra costs due to CAD rework, computer upgrades or training can be minimized by implementing BIM from the initiation stage of projects [18].
The construction process has huge amount of data and information such as enormous specification, drawings and bills of quantities and this information is hard to manage [22]. The practitioners often manage Information and exchange knowledge manually, so, this process consumes valuable time and probably expands cost through loss of data through information exchange process [50]. Won [10] and Azhar [4] suggested that BIM ability to share information easily and quickly among project participants was measured as a most CSF to BIM implementation. Buildings which complex in shapes and systems commonly have many conflicts and clashes between trades, this complex building projects need inter-organizational associations [10,51]. Trust between various project practitioner is crucial to assure success in inter-organizational ventures [51,52]. Due to the nature of work in these inter-organizational projects there is a substantial need for well integration, coordination, and cooperation of project members [53].

CSF 30
Facilitates the sharing of information during a building's lifecycle [8,22,26,40] Several scholars have explained how BIM can improve cooperation during all project stages (initiation, design, construction, and maintenance of a development) [54,55]. Collaboration among project practitioner is a primary requirement for achieving the preferred points of project cost and quality in the construction in-dustry, therefore, there is a significant need to evolve collaboration techniques and a commitment protocol between various project members [11,[56][57][58]. Bryde [18] and Barlish & Sullivan [59] argued that the use of BIM as a collaborative tool has a major impact to project performance. For instance, Won [10] and Erik Eriksson,

Civil Engineering Research Journal
Nilsson [60] support the importance of collaboration between stakeholders to allow information sharing and knowledge transfer. Popov, Juocevicius [26] stated that BIM implementation promote sharing of information during a building's life-cycle, while Kymmell [40] asserted that early collaboration between project stockholders substantially influences BIM implementation. To conclude Lee et al. [61] and Hegazy et al. [62] supported that BIM support efficient collaboration among project participant to share information between them. Also offers an integrated solution for numerous ICT systems. Table 1 illustrates a summary of BIM CSFs [63].

Methodology
This study engaged quantitative data to perform research aim, structured questionnaire was designed for data collection and analysis. The questionnaire was distributed to 68 engineers who have some experience about BIM applications in construction industry in Gaza Strip in Palestine.

Questionnaire design
The questionnaire is divided into two sections. In questionnaire cover page the researcher explain why this questionnaire was developed and identified research aim and objectives as well as mentioned the main sections of the questionnaire. The first section is about respondents' personal information and divided into five question about respondent's gender, education level, nature of work, position and work experience respectively. Second section of the questionnaire contain thirty questions about factors that lead to success in respondent's company in BIM implementation.

Questionnaire verification
Face validity: The validity of the questionnaire designed was tested by present the first draft of the questionnaire to 6 experts with academic knowledge in BIM hardcopy by hand or softcopy by email. These experts made a very helpful and important modification to questionnaire such as: clarify some technical expressions, add some questions and Audit Arabic and English language. These modifications help to developed final version of the questionnaire.
Pilot study: The size of the pilot sample depends on the actual sample size. According to Thomas [64] a sample of round 30-50 people should be enough to identify any substantial bugs in the system. As a result of that, 30 copies of the questionnaire were distributed conveniently to respondents from the target group. All copies were collected, coded, and analyzed by using Statistical Package for the Social Science IBM (SPSS) version 22.

Population and sample
The questionnaire was formed and distributed in March 2019. Target population of the questionnaire includes civil engineers, architects, electrical engineers, mechanical engineers who have some experience about BIM applications in construction industry in Gaza Strip in Palestine. Snow-ball sampling method was conducted as a sampling method in the research. In this sampling method the initial respondents are chosen by non-probability methods and then other respondents are suggested by the initial respondents [65]. Because the number of people who are familiar with BIM implementation is limited and there are limited sources for finding engineers who have experience in this specific topic, snow-ball sampling method can be the best technique to create a network of professional contacts [66]. In questionnaire distribution stage face-to-face and web-based survey was used. A total of sixty-eight copies of questionnaire were distributed and sixty-five of them were satisfactory completed, making the total response rate (65/68) *(100) =95.58%. Snow-ball sampling method helped to obtain a high rate of response and thus increase accuracy.  Table 2, shown that "4D construction sequencing and simulation" was ranked in the first position with RII equals (89.80%). This result illustrates the importance of 4D construction sequencing and simulation for the success of the organization in BIM implementation. This is related to importance of time schedule to construction project. All of projects need to deal with time effectively to save cost and eliminate delays. The study of Sun [37] and Tsai [8] supported this factor as one of the main CSFs facing organization in BIM implementation.

Results
"Clash detection" was ranked in the second position with RII equals (89.54%). This result shows the importance of clash detection for the success of the organization in BIM implementation. This may be due to the ability of clash detection to minimize errors by predicting the conflict and faults in design stage before start construction process on field. In addition, clash detection process will definitely reduce building time. As well as provide well understanding of construction functionalities before onsite construction. Tsai [8] findings support this result and it was ranked clash detection in second position by respondents.
"Support from top manager" was ranked in the third position with RII equals (88.92%). This result illustrates the importance of support from top manager for the success of the organization in BIM implementation. Actually, this result is reasonable because the top manager is one of the most influence member in construction projects. For instance, if one company want to adopt new technology such as BIM, it consults the top manager of the company. So top manager opinion is crucial to decision making. The result obtained aligns with the findings of Tsai [8] which indicated that support from top manager consider the most important critical success factor facing organization in BIM implementation and it was ranked in the first positions by respondents.
"Earlier and accurate 3D visualization of design" was ranked in the fourth position with RII equals (86.15%). This result reveals the importance of earlier and accurate 3D visualization of design for the success of the organization in BIM implementation. Due to the lake of experience of some stakeholders in the construction process, it is difficult to imagine how the final shape of building. So, 3D visualization was found to help all stakeholders to see their construction before it is actually established. The use of 3D models also may eliminate problems associated to off-site buildings. The result obtained is agree with the study conducted by Antwi-Afari [22] and Matarneh & Hamed [30].
"Predicting environmental analysis and simulation" was ranked before the last position with RII equals (59.69%). This means that the ability of BIM to Predicting environmental analysis and simulation is not so important to implement BIM. This is related to availability of data from other reliable sources such as Palestinian Meteorological Department. In addition, the environmental conditions in the Gaza Strip are moderate and do not significantly affect the construction process. As well as The rate of rainfall is relatively low compared to other countries. This results in line with the conclusions of Antwi-Afari [22].
"Providing BIM models for offsite prefabrication" was ranked in the last position with RII equals (59.69%). This means that the ability of BIM to provide models for offsite prefabrication is not important to implement BIM. This results may interpret as project in Gaza Strip not very complex to build offsite prefabrication models to it. And other factor is more important in case of Gaza Strip. This result totally disagrees with Antwi-Afari [22] outcomes which ranked Predicting environmental analysis and simulation in the sixth position.

Civil Engineering Research Journal Conclusion
This paper identified thirty of BIM CSFs and these factors were ranked in order of importance. The study explains the importance of CSFs determination to implement BIM in construction industry as a tool to gain BIM significant benefits to the construction projects through project lifecycle. The findings indicated that 4D construction sequencing and simulation, clash detection, support from top manager, earlier and accurate 3D visualization of design, improved construction project performance and quality, effective cost estimation, more training programs for cross-field specialists in BIM, and managing people resistance to BIM change was the most important CSFs for implementing BIM in construction industry in Gaza Strip. Providing BIM models for offsite prefabrication, predicting environmental analysis and simulation, and increase trust between various project practitioner was ranked in the last positions by respondents.