What is BIM?
The importance of BIM is really the I (information) bit, the geometric data, non-geometric data, and documentation required to design, engineer, construct, maintain, and demolish these assets.
The B (building) has nothing to do with restricting to buildings, it can also refer to other types of built assets we use in our day-to-day lives, such as infrastructure projects (e.g., linear assets; roads, rail, pipe networks, etc.).
The M (modelling) means more than just modelling in 3D it simply means the creation and structuring of information into a visual and coherent form, e.g., creating a spreadsheet in excel is a form of modelling.
In construction, there are two approaches to creating and managing digital models: CAD- and object-based. The first approach is CAD-based workflow, which uses Computer-Aided Design (CAD) software to create 2D and 3D drawings of a building or structure.
A designer uses CAD software to create detailed drawings and plans for construction projects, such as architectural, mechanical and electrical drawings. The drawings are created using lines and shapes; each line or shape is a separate object. These drawings are used for construction but also fabrication and construction coordination.
The second approach is object-based workflow, which uses Building Information Modelling (BIM) software to create a digital model of a building or structure made up of objects. A BIM manager uses BIM software to create a digital model that contains the building elements and their properties and relationships. These objects are linked, and changes to one object can affect the other objects in the model, providing a consistent and accurate representation of the project.
BIM software lets me visualise the building in 3D and extract 2D drawings, schedules and cost estimates. It also allows me to perform simulations and analyses on the building’s performance during its life cycle.
CAD-based workflow is mainly focused on creating detailed drawings and plans for construction. In contrast, object-based workflow is focused on creating a digital model that allows for better coordination, visualisation and building performance analysis during the building’s life cycle.
Integrated: All information is pulled together using parametric, object-based modelling in which non-geometrical data is embedded within geometrical objects.
Digital: Developed by digital technology rather than paper-based mechanisms.
Coordinated, reliable, shareable data: Created in a Common Data Environment accessible to all relevant team members so the information can be shared and coordinated rather than developed in silos.
All project phases: Not just about design; it’s about the whole lifecycle of a built asset.
There are several key misconceptions about Building Information Modelling (BIM); we will choose the top five:
1. A magic solution to all errors: BIM is not a magic solution. It is a tool that can assist in identifying and resolving errors, but it still requires human input and oversight. BIM models can only be as accurate as the information input into them. Inaccuracies or errors in the data can be carried through the entire project, and it is the users’ responsibility to ensure the information’s accuracy and completeness. BIM is also not a one-time investment; it requires ongoing investment and maintenance to ensure the accuracy and completeness of the information.
2. A 3D CAD model: BIM is not just a 3D CAD model; it involves creating and managing digital representations of the physical and functional characteristics of a building. This includes not only the geometry of the building but also the data associated with it, such as cost, energy consumption, maintenance, and lifecycle information. BIM also involves collaboration and coordination between all stakeholders to ensure that the building is designed, built and operated most efficiently and effectively.
3.A piece of software: BIM is not just a piece of software; it involves creating and managing digital representations of the physical and functional characteristics of a building or infrastructure. This includes the geometry and the associated data, such as cost, energy consumption, maintenance, and lifecycle information. BIM also involves collaboration and coordination between all stakeholders to ensure that it is designed, built and operated most efficiently and effectively. The software is just a tool that facilitates this process, but BIM is more than just the software; it’s a process, a philosophy and a culture.
4. A Process exclusively for designers: People may think BIM is exclusively for designers because the initial stages of the BIM process, such as architectural and engineering design, are typically led by architects and engineers. The design team uses the BIM software to create the 3D model and all the associated data, which is BIM’s most visible aspect. However, BIM is not just a process for designers; it is a multidisciplinary process that involves collaboration and coordination between all stakeholders involved in a building project, including owners, contractors, and facility managers. BIM can be used throughout the entire lifecycle of a building, from the initial design phase through construction, operation and maintenance, and eventual demolition or retrofitting. It enables all stakeholders to access the same information, make better decisions, and ultimately, deliver a better-performing building and infrastructure.
5. A replacement for human thinking: BIM is not a replacement for human thinking, it is a tool that can assist in identifying and resolving errors, but it still requires human input and oversight. BIM models can only be as accurate as the information input into them, and it is the users’ responsibility to ensure the information’s accuracy and completeness. BIM requires human interpretation and decision-making to determine the best action when conflicts or errors are identified. BIM is a tool that can support and enhance human thinking, but it is not a replacement for it.
Although BIM is Building Information Modelling, many in the industry now refer to BIM as “Better Information Management”.
So, what is BIM? Here we have Revit. We can see the building. We can get inside the building. We can see green chairs; we can see tables and walls. We can see everything inside the building. You can look at a plan. And look at its occupancy. Look at the different rooms. We can even look at the schedule. It’s a door schedule.
We can select the wall and get all of the rich information from the wall. We can look at the building, but we can also look at the whole facility. Here we have the road, the A19 Silver link roundabout. We can get inside the model and look at an individual pile. And get all of the depths and how much concrete and steel is in that pile. We can look at the reinforcement weights. For each of the different levels and piles and the steelwork weights. We can look at embodied carbon.
We can even look at a cross-section and measure within the bridge. Here you can see. The make-up of the road. You can see the model. We can move the model. You can even get inside the model. You can select critical assets. Like the barrier and get all of the information. The model is there to view, plan and use for design review. What’s even better as you can get in like you’re driving down the road. You can see all of the street furniture and even negate around the roundabout as if you were driving that car.
We can even do rehearsals and see. The actual against the planned. So, this is what BIM is.
Here are a few benefits of Information Management. Let’s concentrate on a few:
Downstream uses for Facility Management (FM): The digital models created using BIM serve as a comprehensive repository of information that can be used downstream in the building’s lifecycle. Regarding facility management, BIM models can provide valuable insights into building systems and components, their interactions, maintenance schedules, and more. This information can be instrumental in preventive maintenance, reducing system downtime, optimising energy usage, and planning renovations or expansions.
Reduction in costs associated with planning, design, construction, and operation: A BIM model is essentially a virtual representation of the building, complete with all its physical and functional characteristics. By creating such a detailed model at the planning and design stage, architects, engineers, and contractors can identify and resolve potential issues before construction begins, reducing costly changes later. Further, BIM helps streamline workflows and fosters better stakeholder collaboration, reducing inefficiencies and miscommunication. Over the lifecycle of the building, a BIM model can aid in effective asset management, predict maintenance needs, and optimize operations, all contributing to further cost savings.
Offsite prefabrication with confidence: BIM is a powerful tool for prefabrication and modular construction. It allows for detailed, accurate models to be used for offsite construction with a high degree of precision and confidence. Components can be designed, reviewed, and approved digitally before being manufactured offsite. This ensures that the components fit perfectly when assembled onsite and reduces waste, rework, and delays. Plus, the safer environment of an offsite factory can help reduce accidents and related costs.
Besides these, Information Management with BIM supports better decision-making with more data, provides more predictability with simulations and ‘what-if’ scenarios, improves communication with visual models, and ensures greater compliance with regulations and standards.
We must first understand want a Common Data Environment, or CDE, is. A Common Data Environment (CDE) is a centralised location for storing and sharing information related to a building project. It is a digital platform that allows all stakeholders to access and collaborate on the same information throughout the entire lifecycle of a building, from the initial design phase through construction, operation, and maintenance.
A CDE typically includes various information, such as 3D models, drawings, documents, schedules, and cost data. It also includes tools for version control, document management, and workflows, to ensure that all stakeholders are working with the latest and most accurate information.
A CDE is a crucial aspect of BIM (Building Information Modelling) as it enables all stakeholders to access the same information, make better decisions, and ultimately, deliver better-performing buildings or infrastructure. It also supports compliance with project requirements and regulations, improves stakeholder collaboration and communication, and reduces the risk of errors and inconsistencies.
We will discuss the CDE is more detail towards the end of the module.
The “dimensions” in BIM refer to the different types of information that can be incorporated into the model. The dimensions are often represented as “3D, 4D, 5D, 6D, 7D, and 8D“. We will go through them one at a time.
3D: Three-dimensional geometry, including the physical characteristics of the building, such as its shape, size, and layout.
4D: Adding the dimension of time to the 3D model, allowing for scheduling and coordination of construction activities.
5D: Incorporating the project’s cost estimates into the model, allowing for cost analysis and budget management.
6D: is a process that focuses on the environmental impact and energy efficiency of a building throughout its lifecycle, from design and construction to operation and decommissioning, enabling sustainable management and decision-making.
7D: including the operational and maintenance aspects of the building in the model for facility management and energy analysis.
8D: adding the health and safety measures of the project in the model to ensure safety.
It’s worth mentioning that using an additional “D” does not always mean that it should be considered a standard or a common practice in the industry; different countries, states or companies can have different interpretations of these dimensions.