Building Information Modeling

The three-dimensional geometry of a building is a vital prerequisite for Building Information Modeling. This chapter examines the principles involved in representing geometry with a computer. It details explicit and implicit approaches to describing volumetric models as well as the basic principles of parametric modeling for creating flexible, adaptable models. The chapter concludes with an examination of freeform curves and surfaces and their underlying mathematical description.

When modeling buildings and infrastructure systems using a computer, it is not sufficient to look solely at geometric data; semantic data also has to be considered. This includes, for example, data about construction methods, materials and the functions of rooms. In order to properly describe and structure this type of information, several different data modeling concepts are currently being applied. This chapter introduces the most essential data modeling notations and concepts, such as entities and objects, entity types and classes, attributes, relationships and associations, aggregations and compositions as well as specialization and generalization (inheritance). Finally, we examine current and future challenges related to data modeling within the AEC/FM domain.

An important part of the BIM methodology is the consideration of processes that create, modify, use or pass on digital building information. The planning and coordination of such BIM processes is one of the many important tasks of a BIM manager. It defines which tasks are to be executed by which persons in what order. In particular, the individual interfaces must be clearly specified. A lean and transparent process definition helps support the introduction of BIM methods significantly. This chapter provides an introduction to formal process modeling, including the modeling languages Integration Definition for Function Modeling (IDEF) and Business Process Model and Notation (BPMN), which are widely used today in the field of BIM process modeling.

The Industry Foundation Classes (IFC) provide a comprehensive, standardized data format for the vendor-neutral exchange of digital building models. Accordingly, it is an essential basis for the establishment of Big Open BIM. This chapter describes in detail the structure of the data model and its use for the semantic and geometric description of a building and its building elements. The chapter concludes with a discussion of the advantages and disadvantages of the IFC data model.

The Industry Foundation Classes (IFC) data model provides a comprehensive, vendor-neutral standard for the description of digital building models. However, the IFC only concerns the data structure. To be truly useful in the context of planning processes, additional specifications are necessary that determine who provides which information when and to whom. To support this, the buildingSMART organization introduced the Information Delivery Manual (IDM) standard. This standard makes it possible to organize data exchange processes in a graphical notation, and to subsequently derive exchange requirements (ER) for data exchanges occurring in this process. The technical implementation of these exchange requirements takes the form of a Model View Definitions (MVD) that accurately specify which entities, attributes and properties may or should be used in a particular exchange. This chapter provides a detailed introduction to the IDM mechanisms. The chapter concludes with an introduction to the concepts of levels of development (LOD).

The Industry Foundation Classes (IFC) data model, developed by buildingSMART, is an important data standard for the exchange of data between BIM process partners. For reliable and consistent data exchange in practice, the IFC import and export functionality of BIM software must function correctly and reliably. Assessment and certification by an independent party offers a way to ensure a consistently high standard of data exchange. To this end, buildingSMART developed and implemented a certification procedure. This chapter discusses the aims of certification, the different expectations of certification, the procedure and its relevance for BIM in general. To conclude, the chapter looks at possible further BIM certificates (modeling quality of BIM data, BIM knowledge, BIM processes) that go beyond assessing just the data exchange interfaces of BIM software packages.

Structured vocabularies are an important means of defining and structuring the meaning of concepts and terms used in the building industry to ensure their consistent use by all stakeholders over the life cycle of a construction. In their traditional form as text documents and tables they are designed for use by domain experts to facilitate the creation and use of unambiguous specifications, requirement documents and mutual agreements. In their digital, machine-readable form, they can be used in a Building Information Modeling context for the semantic annotation of model objects to further enhance exchange and interoperability in data exchange scenarios. This chapter introduces the fundamental concepts, application areas and technical implementations of such terminologies and structured vocabularies.

The Construction Operations Building information exchange (COBie) is a specification that evolved from the idea of Computer Aided Facility Management (CAFM). The specification describes processes and information requirements which streamline the handover of specific data from the design and construction phases to the facility’s operation and maintenance (FM). Until now, the handover comprises a bulk of paper or e-paper documents, but extracting FM relevant information from these documents is considered to be tedious work. Therefore, the key idea of COBie is to incrementally gather and systematically store relevant information in a digital form as soon as they emerge in the project. To realize an effective data exchange and to guarantee market neutrality, the COBie specification suggests open formats, such as Extensible Markup Language (XML), SpreadsheetML or the IFC STEP format. These formats are meant for system-to-system data exchange. However, the implementation status of COBie is still at early stages. In practice, the creation of COBie deliverables is seen as problematic, due to wrong understanding of end users as well as insufficient software implementation. This ultimately lowers the acceptance among practitioners. Nevertheless, the potential benefit for the employer can be significant, if further technical and practical improvements are achieved.

In this chapter, an overview of the current state of the art, future trends and conceptual underpinnings of Linked Data in the field of Architecture and Construction is provided. A short brief introduction to the fundamental concepts of Linked Data and the Semantic Web is followed by practical applications in the building sector that include the use of OpenBIM information exchange standards and the creation of dynamic model extensions with external vocabularies and data sets. An introduction into harnessing the Linked Data standards for domain-specific, federated multi-models and the use of well-established query and reasoning mechanisms to address industry challenges is introduced. The chapter is concluded by a discussion of current developments and future trends.

CityGML is the most important international standard used to model cities and landscapes in 3D with extensive semantics. Compared to BIM standards such as IFC, CityGML models are usually less detailed but they cover a much greater spatial extent. They are also available in any of five standardized levels of detail. CityGML serves as an exchange format and as a data source for visualizations, either in dedicated applications or in a web browser. It can also be used for a wide range of spatial analyses, such as visibility studies and solar potential. Ongoing research will improve the integration of BIM standards with CityGML, making improved data exchange possible throughout the life-cycle of urban and environmental processes.

This chapter describes different possibilities for programming BIM applications with particular emphasis on processing data in the vendor-neutral Industry Foundation Classes (IFC) exchange format. It describes how to access data in STEP clear text encoding and discusses the differences between early and late binding. Given the increasingly important role of ifcXML in the exchange of IFC data, the chapter also examines different access variants such as SAX (Simple API for XML) and DOM (Document Object Model), and discusses the different geometry representations of IFC and their interpretation. Furthermore, the chapter gives a brief overview of the development of add-ins as a means of allowing existing software to be adapted to user-specific needs. The chapter ends with a brief overview of cloud-based platforms and a short introduction to visual programming.

Building Information Modeling (BIM) is characterized by a well-structured creation and exchange of information. In the last years, the term has also been referred to as “Better Information Management”. Due to the high amount of involved parties, which by nature hold contradicting views and interests, the organization of information requirements represents a key factor in the context of project management. The major challenge and chance, lies in improved project and information management achieved by applying BIM and thus, producing and using high-quality information. This chapter presents roles and perspectives to be considered in the building life cycle. Information Requirements and related Information Models are introduced to organize the resulting production of information and its exchange during different project stages. The concept is based on the methodology presented in ISO 19650.

The design, construction and operation of buildings is a collaborative process involving numerous project participants who exchange information on an ongoing basis. Many of their working and communication processes can be significantly improved by using a uniformly structured building information model. A centralized approach to the administration of model information simplifies coordination between project participants and their communications and makes it possible to monitor the integrity of the information as well as to obtain an overview of project progress at any time. Depending on which model information from which project phases and/or sections need to be worked on by which partners, different forms and means of cooperation can be employed. This chapter presents different methodical approaches, practical techniques and available software systems for cooperative data administration. It discusses the different information resources and possible forms of cooperation for model-based collaboration and explains the underlying technical concepts, such as concurrency checking and versioning along with rights and permissions management. Several different software systems available for cooperative data administration are also presented. The chapter concludes with a brief look at future developments and the challenges still to be faced.

Building Information Modeling, as a model-based approach, has various implications for the information and data management of construction projects. In particular, data exchange during the planning and execution of BIM-based projects creates unique demands for the management of data, since the participants involved exchange different kinds of information at various levels of detail according to their individual requirements, and not just once but repeatedly and back and forth. To address this, procedures for structuring, combining, distributing, managing and archiving digital information must be set up and technically supported within a framework for integral model-based project management. It is widely recognized that for the implementation of BIM-based projects and the related collaborative processes, digital collaboration platforms are highly suitable. The British Publicly Available Specification (PAS) 1192 offers a general framework for the implementation of such central platforms based on a so-called Common Data Environment (CDE). The CDE is defined as a common digital project space that provides distinct access areas for the different project stakeholders combined with clear status definitions and a robust workflow description for sharing and approval processes. This chapter presents the technical aspects of the CDE and introduces selected practical aspects.

The BIM Manager has emerged as a new role within construction projects. The implementation and consistent application of a BIM-based approach requires certain regulations concerning project-specific application, the technologies selected, processes, responsibilities and specific instructions for the generation and processing of data. In addition, coordination and support are required throughout the life cycle of a project. This task is rather complex and requires knowledge in engineering and IT, and cannot, therefore, be adequately covered by established functions. It is, however, one of the key factors for the success of the implementation and beneficial application of Building Information Modeling within any project. To date, there is no standardized definition of the function of a BIM Manager. This section deals with the rationale on which this new function is based as well as the related responsibilities, tasks and required skills and expertise. In addition, the chapter discusses the integration of the BIM Manager into the project organization.

The use of BIM planning technologies raises a multitude of legal questions. The core task of construction contract law is to regulate the processes required to employ this planning methodology and the rights and responsibilities of the contract parties. Following an initial discussion of the new contract structures in an international context, the authors cover the regulatory aspects of work organization/process details, rights to data, liability, BIM management and remuneration. The authors place emphasis on what they deem to be the key interests deserving consideration in contract design. Solution approaches of standard international contract models (AIA, ConsensusDocs, CIC) are presented and compared. The authors conclude that BIM neither requires a new paradigm in contract types, nor does it necessitate a new liability regime. Details regarding the use of BIM can be governed in BIM-specific contract annexes attached to individual contracts.

The most important aspect Building Information Modeling contributes to the implementation of engineering design consists in the descriptive interactive visualization of the planned building in 3D, including all the directly related information about product specification, creation, and operation. This creates an in-depth understanding of the construction project and forms the basis for improved coordination between the planners and the parties executing the construction.In addition to the data model and the new visualization possibilities, the three concepts of clash detection, 4D construction process animation, and model checking have emerged to support and control errors in planning; they offer the benefit of additional automation and detailed coordination compared to conventional planning. This section will now focus on the opportunities, benefits, and required conditions of these three concepts, based on practical experience with the customary software.

This chapter describes the application of BIM in structural engineering. In this context, the difference between geometric and analytical models is explained. This in-depth discussion covers the application of the method in the various planning phases – including advance planning, permit planning, and construction planning. Finally, potential future developments are discussed.

This chapter addresses BIM in the context of energy demand calculation and building performance simulation. The focus is on different methods to identify the energy demand as well as on building services engineering, including references to the respective standards and calculation bases. We will present data exchange formats that can be used to exchange and to model the energy-related specifications of buildings and its systems and installations – and we will discuss the necessary requirements and definitions regarding the aspects of geometry, zoning, as well as semantics. The chapter also briefly discusses the current state of software-support for HVAC engineering calculations and dimensioning. Furthermore, we focus on the process chain for the use of BIM in the scope of energy demand calculation and simulation, including a brief discussion of the corresponding Model View Definitions of the Industry Foundation Classes. The chapter closes with an outlook on current research and development projects.

Large to small organizations throughout the entire construction supply chain continue to be challenged by the high number of injuries and illnesses. Although the five C’s (culture, competency, communication, controls, and contractors) have been focusing on compliance, good practices, and best in class strategies, even industry leaders experience marginal improvements in occupational health and safety (OHS) for many years. BIM for construction safety and health identifies three major focus areas to aid in the development of a strategic – as opposed to tactical – response: (a) OHS by design, (b) pro-active hazard detection and prevention at the workplace, and (c) education, training, and feedback leveraging state-of-the-art processes and technology. This chapter explains the motivation for developing a strategic roadmap towards the use of BIM in OHS. It highlights meaningful predictive, quantitative, and qualitative measures to identify, correlate, and eliminate hazards before workers get injured or other incidents cause collateral damage. Using selected case study applications, the potential of BIM in practical implementation as well as the social implications on conducting a rigorous safety culture and climate in a construction business and its entire supply chain is shown.

In the construction industry, a large number of codes and guidelines define technical specifications and standardized requirements to ensure a building’s structural stability, accessibility, and energy efficiency, among others. Today, checking the compliance with the applicable guidelines is an iterative, manual process which is based to a large extent on 2D drawings. In consequence, this process is cumbersome, time-consuming and error-prone. With the increasing adoption of digital methods in the construction industry, most importantly Building Information Modeling (BIM), new technologies are available to improve and partially automate this process. In a BIM-based construction project, digital models that include 3D geometric as well as semantic information comprehensively describe the building to be erected across the different involved disciplines. This rich information provides an excellent basis for automating the code compliance checking process. With Automated Code Compliance Checking, not only a higher degree of compliance with the different regulations can be achieved, but also a significant reduction of effort is possible. The chapter first discusses the major challenges of Automated Code Compliance Checking. Subsequently, representative available software solutions are presented and current research activities are discussed. Finally, an outlook for the development of code compliance checking in the construction industry is given.

Estimating represents an important aspect of the building process that can benefit from computable building information. Quantity take-offs (QTO) are usually performed at different stages of the project and with different purposes (e.g., for cost estimates and auditing). The conventional approach to perform a QTO represents a time-consuming and error-prone process. Relevant building information needs to be extracted from drawings and unstructured documents, which might be outdated or inconsistent. This chapter focuses on the requirements to support BIM-based QTO. Crucial aspects comprise defining a clear project structure as well as establishing a transparent information management. To organize building-related information, the application of a project-specific Work Breakdown Structure (WBS) is proposed. The structure and content of the generated models needs to adhere to the WBS. In this context, geometric and alphanumeric information at various Levels of Detail (LoD) need to be included. Based on these prerequisites, a workflow for an automated generation of QTO is presented.

Building surveying is an important element for as-built documentation as well as for planning and construction in existing contexts. In connection with BIM, however, building surveying faces new challenges. In the past, the results of surveying were typically two-dimensional CAD drawings depicting floor plans, sections, and views. BIM, in contrast, relies on digital three-dimensional building models based on an object-oriented modeling paradigm including semantics, descriptive data, and relationships of building elements. This holistic building modeling approach also impacts the surveying workflow for building measurement as well as the data processing. Nevertheless, the basis for building measurement are geodetic surveying techniques with single-point methods (manual surveying, tacheometry) or aerial measurement methods (photogrammetry, laser scanning) in combination with appropriate surveying software. Also, new developments in context of spatial data capturing (UAVs, multi sensor and mobile mapping systems) rely on these basic methods.

Building Information Modeling offers enormous potential for increasing the productivity of design, production and quality management processes in the field of industrial prefabrication. To this end, construction software for production models needs to fulfill a series of additional requirements compared with typical planning-oriented CAD systems. Automated production systems require extremely precise geometric data, which requires the use of parametrical modeling techniques and support for common data exchange interfaces for production machinery used in the industry.

Three-dimensional printing – often known as additive manufacturing or the layered production of 3D objects – has been the focus of attention in the media at present and a subject that arouses great expectations in the construction industry. While the topic is rapidly emerging, 3D printing has the potential of simplifying key processes in the facility lifecycle, for example, by following design to production principles and reducing waste while increasing the quality of the final product. A pivotal piece in the success of 3D printing in construction is the Building Information Modeling (BIM) method. Since BIM already serves as a rich source of geometric information for commercially-existing, large scale, and automated 3D printing machines, 3D printing robots co-existing with human workers on construction sites will eventually need scheduling and assembly sequence information as well to maintain safety and productivity. As suitable 3D printing techniques and materials are still parts of wider research efforts, applications by early adopters in the construction industry demonstrate how 3D printing may benefit and at some point in the future complement existing construction methods like prefabrication or modularization.

The term “production system” is mainly used in connection with the industry of stationary production. It describes the overall system of controlling and monitoring the manufacturing of goods. Companies generally use internal software systems for their own, specific requirements. Such production systems and the related software systems cannot be transferred to construction projects since the conditions of such projects are very specific and varied; production systems are thus hardly ever used in the building sector. The BIM-based approach, which is finding its way into the construction industry, spans various fields of expertise, is geared towards cooperation and standardization and to an in-depth implementation of digitized data processing; it is therefore well positioned to overcome existing obstacles. Restrictive elements (fragmentation, temporary production facilities, unique product) can now be eliminated through the introduction of a BIM-based production system; project control can thus be improved, simplified, and rendered more efficient. At the same time, the method of operation is standardized throughout the entire project. This approach constitutes a fundamental change to project control in the construction industry, which will shift its focus from people to information in future.This chapter deals with the purpose and conditions of the implementation of a BIM-based production system in construction projects. The relevant information and the modular structure of such systems are described in detail on the basis of practical experience gained in the implementation in various projects.

On-site progress monitoring is essential for keeping track of the ongoing work on construction sites. Currently, this task is a manual, time-consuming activity. BIM-based progress monitoring facilitates the automated comparison of the actual state of construction with the planned state for the early detection of deviations in the construction process. In this chapter, we discuss an approach where the actual state of the construction site is captured using photogrammetric surveys. From these recordings, dense point clouds are generated by the fusion of disparity maps created with semi-global-matching (SGM). These are matched against the target state provided by a 4D Building Information Model. For matching the point cloud and the model, the distances between individual points of the cloud and a component’s surface are aggregated using a regular cell grid. For each cell, the degree of coverage is determined. Based on this, a confidence value is computed which serves as a basis for detecting the existence of a respective component. Additionally, process- and dependency-relations provided by the BIM model are taken into account to further enhance the detection process.

BIM does not only facilitate the design and construction of buildings, but also and especially the operation of these buildings. This chapter argues that the BIM-based operation of buildings can be divided into six work stages: (1) requirements management; (2) preparation for commissioning; (3) commissioning; (4) ongoing operation; (5) change of owner/operator; and (6) data acquisition for existing buildings. During these stages, a structured set of data relevant to the operation of the building(s) is constantly updated. These data sets facilitate multiple use cases occurring during the operation phase, e.g. the operation, inspection and maintenance of technical equipment. The data relevant to the operational phase can either be obtained by the handover of design and construction data or by the collection of data for existing buildings or buildings where the BIM method was not used prior to operation.

Since 2003, HOCHTIEF has been systematically developing Building Information Modeling (BIM) in the framework of the innovative ViCon concept (short for Virtual Design and Construction). HOCHTIEF uses BIM during the tender, planning, and construction phases of major projects. The traditional working processes are adapted towards the new BIM methodology in a sequential and iterative manner. Based on national and international developments, there will hardly be any projects in the near future not relying on BIM.

For Arup, BIM represents a new paradigm for an integrated approach to design. The push towards BIM in the architecture, engineering and construction industry represents a digital alignment with Arup’s existing ‘Total Architecture’ philosophy. Arup has always been at the forefront of new technologies, such as CAD, 3D Design, and project collaboration. The chapter provides details on Arup’s drivers, strategy and the five key activity areas under the implementation program: Governance and leadership, People and skills, Marketing and communication, Processes, Technology.

For a general planner such as OBERMEYER the application of BIM assumes a pivotal role. The focus on computer-aided planning already commenced shortly after the foundation of the company over 60 years ago. Today, the company is committed to establishing generally valid BIM standards and guidelines, e.g., as leading member of buildingSMART Germany or as co-author of the German BIM manual published in 2013. Three sample projects on the current planning front illustrate how BIM can be implemented in practice: the planning of the 2nd principal rapid transit line in Munich, the Auenbach viaduct pilot project and the planning of Al Ain hospital in the United Arab Emirates.

As a global manufacturer, Hilti is much affected from Building Information Modeling (BIM). Based on a detailed analysis, BIM has changed the offering of Hilti to its customers on various levels. Hilti has developed software and services for the different project stages to provide a holistic support for the clients. The software tools aim for a direct integration of the customer workflow. They help to conduct the regular use cases in a fast and efficient way. The services complement the offering to cover special requirements of the projects. Hilti is already integrated in the design phase to find the optimized solution for the fastening and protection requirements.

Modern construction projects can be designed, built and operated more efficiently and to a higher quality when knowledge is shared quickly and transparently. With BIM.5D®, STRABAG SE has been advancing the vision of a “digital construction site” since the late 1990s. The “5D” stands for the 3D model + time (4D) + process data (5D), thus adding all relevant process information to the product-oriented building information model. BIM.5D® involves the client and all project participants from the start of a project and facilitates the interdisciplinary gathering and analysis of data to generate valuable information. One of the many benefits BIM.5D® offers is the transfer of knowledge that increases the quality and the efficiency of the final product. Since project data is digitally captured, combined, and linked over the entire lifecycle of a construction project, the result is a comprehensible, transparent and resilient information network for everyone involved in a project.

This chapter illustrates the current status of the implementation of Building Information Modeling and addresses questions that still need to be answered. In addition, there is an outlook on expected developments in the near and distant future. In particular, the potentials of autonomous construction methods are discussed.