1. Introduction

For the past decades, awareness of the earth and the environmental situation was not considered an important issue until the late 20th century, when technology and industry, in addition to the growing population, were negatively affecting everything around them. This environmental impact will significantly affect all following generations, particularly in developing countries. Therefore, innovative ideas, principles, and studies between dedicated professional roles (e.g., environmentalists, architects, ecologists, etc.) introduce new ideologies to develop technologies aiming to compensate for the adverse impact of fast-growing developments to achieve sustainable solutions through collaboration and beneficial decision making. Hence, throughout history, information has been developed to involve new sustainable methodologies to assess previous work results, assign new practices and techniques to raise the influence of sustainability momentum, and increase awareness of the best environmental practices through different advent technologies ^[1]. Green construction requires and suppresses information and data to support, identify, and review the negative impacts a project can be exposed to, such as waste, energy consumption, or pollution, through continuous development efforts to support the sustainability approaches and environmental aspects.

The construction industry significantly affects the environment; it is considered a paramount reason behind energy use, water waste, waste generation forming landfills, the destruction of habitats, unpleasant health conditions, and many other negative impacts. Thus, according to the UN Environment Program (UNEP), construction is responsible for enormous burdens and various effects, 36% of energy consumption, 37% of all energy-related CO₂ emissions, and 40% of solid wastes through construction and demolition, in addition, to consuming almost 12% of global water usage ^[2]. Not only does construction affect the environment but it also directly impacts human health, productivity, and efficiency because of the indoor environment and materials used. Hence, professionals encourage using new building technologies integrated with standards and policies; the vital concepts introduced to practically apply the vision of saving the environment. Furthermore, developing strategies such as green buildings, smart cities, and environmental were introduced to lessen the negative impact of the building sectors by many means such as using energy utilizing conservation tools, energy performance systems, and renewable energies ^[3]. For example, new building technology approaches to sustainable development goals might require developing cities through green construction, sustainable design approaches, and reducing the consumption of scarce resources to lessen and manage waste ^[4]. In addition, social goals rely more on human comfort and health through better indoor environmental qualities to reduce negative impacts and to create a good living or working environment within the building.

Adopting superimposed methodologies is imperative for Egypt to curb negative environmental impacts and build a sustainable living environment that respects human health. This research aims to shift toward sustainable and green buildings in Egypt through a local rating system and promote efficient energy, resource, water, and indoor environmental quality. It also aims to develop a framework that integrates BIM and the local Egyptian sustainability rating system to assess sustainability in construction projects at the early design stages. The scalable methodology aims to bridge the gap in implementing new technologies and work methods leading to Egypt’s low-carbon, highly efficient, and greener buildings. The research includes developing a dynamic BIM tool incorporating sustainability aspects and using simulation tools to enhance performance and meet the green pyramid rating system (GPRS) credits. A Revit API plug-in Sustainable “GPRS BIM-based Tool” is also introduced to automate sustainability assessment and specify the achieved certification level.

2. BIM Tools for Sustainability Assessments

Green building design remains a complex task that requires the adoption of the integrated design process (IDP), where BIM can be used to improve decision making in building design. An elementary means of using BIM to improve decision making is to reduce the work involved in evaluating multiple options early in the design process and save time ^[5]. Information management uses building information modeling through the ISO 19650 ^[6] series title, which generalizes information requirements processes since sustainable building assessment requires information exchange from various building professionals. Pikas et al. ^[7] further argued that there is a general lack of theory on building design where the model information can be exchanged between various software tools. In contrast, data interoperability is the ability to exchange and use information. The model information is combined with the model buildings to design and use the various inputs to simulate and analyze the building performance and different types of consumption, including energy, water, and others ^[8]. The various analyses use the latest software technologies such as ArcGIS, EnergyPlus, and Insight by effectively sharing models within the OpenBIM-facilitated common data environment (CDE) and quickly prioritizing and identifying the interoperability of different sustainability tools to gain an overall environmental assessment ^[9]. The CDE may follow the standards that are assessed to develop the methodology of the sustainability approach in the ACE industry for construction environmental impact assessment (EIA) through the environmental product declaration (EPD) and other considerations ^[10].

BIM-enabled 6D sustainability analysis can also assist in identifying potential risks and issues that may arise during the operational phase of the building, allowing for proactive measures to be taken to avoid or mitigate these risks. Additionally, it can help in the decision-making process for retrofitting or refurbishing existing buildings to improve their sustainability performance. By simulating various scenarios and analyzing their potential impact, stakeholders can make informed decisions to optimize the sustainability of the building while minimizing the associated costs. BIM 6D simulation is essential for construction projects’ sustainability assessment and appraisal processes. For instance, the main objective of “The Energy Performance of Buildings Directive” from 2021 is to require all buildings to be nearly zero-energy buildings (NZEB) ^[11]. To mitigate these impacts, the BIM process uses the digital interconnectivity between various BIM software for the needed actions since one software does not perform all of the requirements. BIM software and the wide range of functions for different BIM solutions with brief descriptions assist in choosing the right BIM software, which can be challenging, especially since various sustainability-related practices and measures are being introduced ^[12]. In addition, multiple constraints influence software choices, such as price, capabilities, and interoperability requirements. Additionally, through BIM, the user can rapidly test numerous options of varying complexity and quantify and test variable productivity and efficiency due to better communication and integration, accelerating the project timelines ^[13].

3. Development of Green Building Rating Tools

Green building rating tools (GBRT) or green building assessment tools (GBATs) are established as sustainability metrics for assessing green building design. Green building environmental rating systems (GBCs) are different worldwide; thus, they have similar structures through different levels of detail in evaluating buildings according to various approaches and categories such as the site, energy consumption, water efficiency, material use, indoor environment, and innovative solutions. Moreover, GBCs significantly aim to reduce energy, carbon, and water consumption, raw materials, and waste production. There are various GBCs for the construction industry; for instance, the most popular rating system is leadership in energy and environmental design (LEED), building research establishment environmental assessment methodology (BREEAM), Energy Star, Well, Green Globes and German sustainable building council (DGNB) ^[14]. Examples of middle east green rating systems include the green pyramid rating system (GPRS) in Egypt, the global sustainability assessment system (GSAS) in Qatar, the pearl rating system (PRS) in UAE, and the ARZ building rating system in Lebanon ^[15].

On the other hand, many initiatives have sought procedures to obtain comfortable buildings using various sustainable building rating systems as assessment tools to examine the expected performance of the whole building and translate that into an overall assessment that allows comparing the building against the regulated benchmarks or the other facilities ^[16]. However, there are a lot of “Voluntary Green Tools” to explore and analyze the building according to the needed function, such as frameworks, checklists, rating, ranking tools, analytical tools, various software with expert systems, and organizing tools ^[17]. Although there are numerous methods for assessing the sustainability performance of a building, the green building assessment method developed by LEED is the most popular used worldwide due to its comprehensiveness and simplicity. Thus, countries must develop rating systems based on local standards to assess their sustainable construction practices and reach sustainable design aims ^[18]. Despite the numerous contributions toward a sustainable built environment, as shown by the abovementioned green building assessment tools, each country believed that the examined certification systems needed strong adaptation to meet the needs of the local climate, social, cultural, environmental, and economic conditions ^[19]. The GPRS is an Egyptian rating system that aids in assessing sustainable construction practices and achieves sustainable design aims. It captures the local context of Egypt and its national priorities. The GPRS is developed with the specific goal of ensuring that sustainability assessments in Egypt accurately reflect the country’s unique context and priorities through different perspectives. It takes into consideration the specific environmental challenges that are present in Egypt, such as water scarcity, desertification, energy efficiency, and pollution, which are key environmental challenges in Egypt. GPRS also considers the urbanization challenges that Egypt is facing, such as rapid population growth, informal settlements, and pressure on natural resources. Therefore, the system encourages the development of green buildings in urban areas while promoting sustainable urban development toward desert areas since buildings consume significant amounts of natural resources during their lifespan. Implementing green and sustainable principles can help to reduce the negative impact of buildings on the environment and provide economic benefits throughout the building’s lifecycle. Moreover, GPRS incorporates the national priorities outlined in Egypt’s sustainable development strategy (SDS), also known as Egypt Vision 2030. The SDS goals related to the environment, energy, and urban development are specifically addressed by the GPRS certification levels, which provide a practical framework for building owners, designers, and governmental authorities to collaborate and achieve sustainability.

The GPRS assesses buildings using seven main qualitative categories to address the contents and dimensions. These categories are sustainable site (SS), energy efficiency (EE), water efficiency (WE), materials and resources (MR), indoor environmental quality (EQ), management protocols (MP), and innovation and added value (IN). The scoring system is a quantitative weighted score to calibrate building performance and determine the compliance control status. The summation of the collected points is 100% points, in addition to a 5% bonus. The GPRS certification levels are credit-based to control the rating process and determine the building certification and level of rating; up to five green pyramids can be awarded for sustainability. The certification levels are Platinum (greater than 80%)—five pyramids, Gold (65–85%)—four pyramids, Silver (50–60%)—three pyramids, Bronze (50–40%)—two pyramids, and Certified (40–30%)—one pyramid. Several research efforts have been made to analyze GPRS.

The GPRS needs to be designed and implemented with an integrated approach that uses a systematic process that includes stakeholders from all levels of society (e.g., policymakers, decision makers, designers, and contractors). Moreover, the government should empower and encourage the GPRS policy at the federal level to ensure consistency and then integrate these standards into the urban planning laws of the cities. This approach helps promote incorporating green design principles, sustainable building practices, and technology into construction planning and operations in urban areas of Egypt. On the other hand, the authors examined various aspects of building sustainability and rating systems and explained different BIM-based building information modeling (BIM) frameworks and sustainability approaches.

For instance, Edeisy and Cecere ^[20] presented a study on developing the current building energy efficiency code (BEEC) to consider the gaps, needs, and requirements by providing guidelines that help increase energy efficiency in the residential sector in Egypt in addition to developing training to provide the teams with technical knowledge and required skills of the current code compliance. Younan ^[21] conducted a comparative study, comparing different rating systems to construct a new rating system that fulfills the Egyptian construction sector requirements. Karmany ^[22] compared three rating systems (LEED, GPRS, and TARSHEED) to identify which is more applicable in Egypt and highlighted that gaps should be considered in future versions of the assessment system and should follow the technical knowledge and the country’s local strategies and needs. Mohamed ^[23] recommended developing a roadmap to mandate BIM in the Egyptian construction industry and develop BIM best practices and implementation process platforms. Hazem et al. ^[24] introduced a sustainability research roadmap and proposed a new energy rating system for new and existing buildings.

Hazem and Fahmi’s ^[25] study also introduced a new rating system for new construction in Egypt, addressing all categories using the AHP as a step toward implementing green concepts. Attia and Dabaieh ^[26] adopted a dual mixed approach to ensure the importance of developing the GPRS certification rating system to meet the climate, social, cultural, environmental, and economic needs according to the local conditions, and adapt them to the local construction practices. Meanwhile, Ammar et al. ^[27] mentioned that GPRS still needs more development and improvement, although GPRS was developed based on the international US LEED. Moreover, it is essential to develop the system as an idea that incorporates all project participants by integrating architectural, constructional, electrical, and mechanical with environmental experts from the pre-design and design stages through the construction, processing, and maintenance phases. On the other hand, Cascone ^[28] examined the potential integration between LEED and BIM. Various integration techniques, such as third-party software data exchange, cloud-BIM, and plug-in development through API, were analyzed for their applicability in the early design phase. Additionally, BIM Toolkit ^[29] was introduced as a UK-initiated part of the Level 2 BIM package of tools and standards. Thus, the main challenge for implementing sustainable construction in Egypt and developing improved green building certification systems is encompassing critical green building sustainability criteria that can be used to validate the actual credits assessable with BIM technologies and minimize the gap between simulation outputs from analysis tools and real-world values ^[30]. However, the construction industry in Egypt is lagging in adopting new technologies aiming to improve the quality of construction ^[31].

4. Research Gap

The proposed approach has identified several research gaps that need to be addressed, challenges related to GPRS sustainability assessment issues, and the development of an indicator tool. These areas include the need for a better understanding of the integrated project delivery method and sustainability assessments, a dependency on international frameworks and methodologies, the lack of integration between BIM technology and GPRS guidelines, the absence of decision-making criteria for engaging BIM methodologies and sustainability rating systems, and the absence of an intuitive interface to incorporate more advanced sustainability criteria into the decision model. Addressing these research gaps and challenges is critical for making the building certification process more accurate from the design’s early stages and improving sustainability assessments in the construction industry.

5. Proposed Framework

The research proposes a framework to illustrate the feasibility of construction projects using BIM for sustainability rating analysis in the design and construction to assist the building industry in improving its environmental performance. The framework utilizes automated BIM-authorized tools and a developed Revit API plug-in to contribute to disseminating sustainable construction. These tools allow multidisciplinary information integration for faster, more accurate, and more efficient sustainability evaluation and analyze and simulate energy performance results to obtain alternative design options. Furthermore, the framework acts as a sustainability decision-making support tool in a collaborative platform to achieve better sustainable buildings by ranking the sustainability certification level based on the various physical features, performance assessments, and calculations of the combined results from the different categories of the proposed design of any building typology. The assessment is carried out according to the GPRS local sustainability rating systems. As such, a building can be classified as Denied, Certified, Bronze, Silver, Gold, or Platinum.

The proposed framework identifies a roadmap to introduce GPRS integrated with the latest BIM technologies and tools for building assessment within Egypt through a comprehensive screening of the initial effects of sustainability factors. The framework builds a relationship between the green building rating processes and integration functionalities of BIM. The adopted methodology corporates the design processes to pursue the certification and achieve the ideal design solutions according to specific principles and fundamentals that need to be examined to adopt the green building approach and needs. The stages depend on the efficient coordination of people, tools, and technology as sustainability pillars combined with the BIM pillars of policy, process, and technology.

Figure 1 illustrates the methodology adopted for this study, which includes several stages. In the first stage, the project brief, goals, information, and requirements are studied and defined, and the available information and data are analyzed, checked, and documented. The second stage involves preparing the fundamental design and sustainability modeling requirements using BIM authoring tools. This is followed by using BIM simulation tools to assess the sustainability of the design, which can be divided into assessment sustainability tools and rating sustainability tools. The assessment tools develop several configurations of passive and active systems that can be applied to the building. These tools help each profession choose the most applicable option from various alternatives. The rating tools, on the other hand, assess the environmental impacts of the building design based on specific guidelines or systems. The goal is to ensure that the environmental impacts are assessed and that the building design achieves a certain level of sustainability. This study incorporates technology to create a Revit plug-in as a sustainability BIM rating tool to achieve higher compatibility. The tool evaluates the sustainability of the proposed building based on the GPRS-collected scores. According to the GPRS sustainability certification levels, the calculated total score determines the sustainability certification level of the building model, which can range from Denied, Certified to Bronze, Silver, Gold, or Platinum.

Figure 1. Proposed Framework Development Stages.

5.1. Data Collection

The first step is to develop the green BIM decision process and create the necessary BIM documents for each project delivery stage. The team is built to determine the feasibility of achieving a GPRS certification level, and a general BIM execution plan (BEP) for the green BIM process map Level 1 is created. The data relevancy is elaborated, and potential BIM tools and software are determined to check the eligibility and efficiency for evaluating the building's performance. The project team’s early involvement is necessary to perform an efficient IPD, and the RACI responsibility matrix chart defines each project team member’s roles. The management and documentation start from the planning stage, as depicted in Figure 2. The design team determines the content, considers the client and other stakeholder requirements, and sets specific project green building targets and performance measures using GPRS credits and points. Data preparation, acquisition, and documentation are also carried out to clarify the project’s scope and provide comprehensive information. Design development manages the gathered information data and prioritizes the goal of fulfilling the needed credit requirements to achieve certification. An assessment database is created and updated dynamically to include information related to green specifications, technical information, materials, and manufacturers. Finally, the team implements the system and submits all necessary documents for certification review and approval to verify the GPRS Checklist, ensure the credits are implemented, and report on the project’s progress.

5.2. Digitalize Sustainability Using BIM

The second stage of the BIM sustainability process involves the physical implementation of the BIM using a sustainability evaluation as one of its uses. Custom-made families with shared parameters are developed to create a logical flow of related data and provide architects, designers, environmental specialists, and the rest of the team with different building elements and components to assess decision making in the design development process. An external BIM database is created for sustainable materials, which is continuously updated with new innovative materials and specifications. The parametric Revit template and schedules ensure efficient management and improve interoperability for any project delivery method. The created parameters may be updated or modified, and new parameters may be added as needed during the sustainable design phase.

Figure 2. Management and documentation workflow.

5.3. Model Development

The data extraction according to the interoperability characteristics and enhancements is vital in this step because the users directly link the BIM model to the external database. According to the extracted data from the previous results, the user constitutes the BIM-based model for implementing the proposed building to form a 3D model using a digital BIM authority tool for each constructional element. This is carried out to identify the current building geometrical situation and establish a baseline building mass and volume for the proposed design. The preliminary data required are the project information and physical properties. Then, the user inputs all of the properties of the objects to incorporate the information into the model before starting the modeling phase using Autodesk Revit. Next, the geographical location of the building is defined by the ‘Internet Mapping Service’ and provides the project site’s exact location and the nearest weather station. In addition, spaces and rooms should have a defined name associated with their area and volume. Finally, the created space defines the initial room functions, zones, and activities for the first step of proper energy calculations after creating the model configuration.

5.4. Conduct Simulation Using BIM

In this building sustainability analysis stage, the user identifies and selects the list of sustainability indicators assigned to each sustainability category. Data exchange and synthesis of information files are the most critical interoperability factors between the various BIM applications and analysis programs to review the selection of techniques and processes for sustainable solutions. The correct information is key to gauging the valuable contribution of each criterion, ensuring the consistency of the best practical environmental options, and evaluating the sustainability performance of a building. First, the environmental baseline for a pre-assessment simulation is conducted to quantify the different environmental impacts for the whole building on the chosen project site location. Then, these performance model simulations test the retrofitting solution options while considering the study limitations to determine the base analytical models and the potential savings or improvements.

5.5. Calculations and Schedules Generations

In this practice, the automatic extraction of specific data required from different databases and calculation tools is enabled to ensure a diverse visualization design for an easy user interface from the built-in parametric information in the form of comprehensive schedule views. The schedules are generated automatically based on the updated input information and may include building information, materials, components types such as room areas and volumes, detailed calculations, and materials takeoff schedules. The quantity takeoff data can be exported to a spreadsheet or an external database, or imported into another BIM tool. In addition, the schedules show the results of the calculations and can be exported in an Excel format for documentation and submission purposes. Dynamo is used automatically to generate, export, and import these data from/to the developed BIM model. The developed analysis system aims to optimize the building materials selection process. The components are customized and developed in the new GPRS BIM sustainability-based tool using the predefined GPRS families.

Figure 3 illustrates the output monitoring process for credit recheck after assuming how these factors will impact the building design and illustrates how to evaluate the project’s compliance with the potential GPRS-collected points for each credit. In addition to comparing these alternative sustainable impact assessments and the steps, the data are extracted automatically for GPRS certification, documentation, and other enhancements. The building component selection criteria provide the designers with the required information related to the environmental criteria to reach green construction with various sustainable design options.

Figure 3. Proposed GPRS credit calculation process.

5.6. BIM Plug-In Development

The building sustainability assessment stage demonstrates practically the capabilities of seamless interoperability between the proposed GPRS BIM-based sustainability plug-in tool, developed in Autodesk Revit using a developed application programming interface (API). First, the user loads the plug-in into the BIM authority tool (Revit) with a graphical user interface (GUI). The tool uses the API to allow the user to extract the needed data directly and automatically from the BIM model. Then, the calculation formulas rely on integrating the input data from the user. The tool evaluates the indices, including the potential GPRS points that can be achieved. Even if the user changes the chosen materials or component scores as data input, the tool will automatically read the updated potential accumulated credits according to the category. The credit scoring systems acquire the needed sustainability parameters and then calculate the total potential sustainability final score. The integration extracts the weight factors for sustainability criteria from users and ranks the categories list of total potentially earned points for the project. This score is compared with the GPRS assessment standards and obtains the certification result. A summary report is generated to illustrate and detail the total points achieved for each category, and the sustainability certification level is certified as Bronze, Silver, Gold, or Platinum. The BIM-based tool assists the designers in modifying their designs from the early stage to adjust the estimated scores before submitting the documents for the final review. Even after exporting the result, it can be used for other purposes such as proof, documentation, design, and operations guidance.

The proposed framework provides several calculations and practical approaches through four significant steps to assess the sustainability level of the building according to the green pyramid rating system (GPRS) integrated with building information modeling (BIM). First, the sequence of the considered steps starts with providing and collecting project data and designing BIM documentation, then, using Revit as a BIM authority tool, the BIM model is developed. This is followed by performing sustainability modeling and conducting assessments using various BIM tools, methods, and technologies to provide a comparative analysis. As a result, the framework secures more accurate and consistent project information throughout the lifecycle compared with conventional management methods. In addition, it assesses selecting the most appropriate sustainable design solutions using energy efficiency approaches, determining better water-saving usage strategies, and choosing the most compatible materials for better green and sustainable constructive decisions after evaluating the performances and providing modifications. Thus, the process of developing this framework reduces the lack of accurate and adequate documentation by using the integrated information to combine BIM geometrics with the local GPRS sustainability guide while considering alternative design factors to support the decision makers through an organized BIM workflow. Finally, the developed plug-in includes a GUI that uses the API as a Revit plug-in, which allows users to automatically extract data from a BIM model and evaluate the potential sustainability of a building project. The plug-in includes calculation formulas to determine the building’s sustainability level according to the GPRS.

6. Conclusions

The proposed framework incorporates BIM methodology and project management to simplify evaluating the overall GPRS (green pyramid rating system) and documentation processes. The BIM-based tool developed for this framework has successfully verified the optimal design retrofit solutions for the building, resulting in a Gold certification level with a better sustainable design tool through a local office building case study in Egypt. The framework guides the design team in determining the building aspects during the early design stages for various sustainability objectives. It incorporates the BIM methodology and project management to simplify the evaluation of the overall GPRS and documentation processes by preparing the theoretical foundation for sustainability solutions. Further, it integrates the simulation approach using the developed GPRS Revit template with embedded GPRS categories by implementing the technical details using the created shared parameters for assigning the sustainability criteria within the BIM model. This research can be extended in future studies to include updating the created materials database with the necessary local green properties and interfacing it with BIM software to produce a suitable BIM model containing the required green database, considering the economic aspect of both the conventional and circular approaches by adding other decision metrics, such as the cost of operation in addition to achieving more sustainable development goals by considering social aspects. This research can be extended in the future to validate the outputs of the proposed GPRS BIM-based tool against different project types such as residential, commercial, and educational projects. The potential GPRS BIM-based tool users can also subjectively compare the tool and system behaviors, based on their intuition, to decide whether the tool and its results are acceptable and reasonable. They can assess the completeness, depth, practicality, and realism of the proposed tool.