Glossary October 12, 2020
Updated 18 January 2024 by James Ocean

BIM dimensions explanation and benefits. 2D, 3D, 4D, 5D, 6D, 7D and 8D BIM.

Table of Contents

To simply put this, building information modeling (BIM) is a process of using a well structured digital information to deliver, design, operate, and also hand over building projects.

BIM is a process that is becoming increasingly popular in the AEC (architecture, engineering and construction) and building industry. Building sectors such as the architectural sector, engineering sector, and the construction sector – each have defined purposes and unique benefits of BIM. For example, in the construction sector, BIM helps to reduce wastage of building materials and also virtually assess the risk of the project. Most importantly, BIM helps to detect where clashes take place and also make sure there is a reduction of mistakes on site, etc.

Perhaps the major and overall advantage of the BIM process is that it supports the construction process and the design process from scratch to the whole package and beyond for all the parties that are involved in it.

It is safe to say BIM – building information modeling has revolutionized the building sector across the world by enabling any authorized person, from any part of the world, access the building information and communicate and collaborate with people on-site.

That being said, it is then of utmost importance that builders, designers, and project sponsors alike fully understand the BIM models, BIM software, and its components.

What are BIM dimensions?

BIM dimensions give you a better understanding of your construction project and the process of linking additional dimensions of data to your building models. In this section, we will explore different BIM dimensions, namely 2D, 3D, 4D, 5D, 6D, 7D, and 8D BIM dimensions.

2D BIM dimension

2D dimension is the earliest form of construction models. It constitutes a simple X-axis and Y-axis. These models are generally made by hand using manual processes or through the use of CAD drawings.

3D BIM dimension

3D BIM is arguably the most popular BIM dimension that all construction companies are familiar with. It is also referred to as a coordinated model.

3D represents the 3-dimensional geographical structures of a building – that is the X-axis, the Y-axis, and the Z-axis of a building. 3D BIM entails the creation of graphical and non-graphical building information for the sole purpose of sharing it in a common data environment (CDE).

BIM 3D models are employed to schematic designs, design development and documentation, construction documentation, and record drawings. By using 3D BIM, you will be able to keep your workers updated on the latest design trends.

What are the benefits of 3D BIM dimension?

  • Visualization: Throughout the entire project, 3D BIM would give you a full 3-dimensional visualization.
  • It helps to check for possible collision
  • It aids communication among the workers
  • Ensures transparency during the entire project.
  • Creates a detailed model of the impact the project would have on the environment.

4D BIM dimension

A 4 dimensional BIM model reveals additional dimensional information, known as a scheduling data or time element – it is the main reason why 4D BIM is often referred to as construction sequencing. This model starts with a 3D BIM, and then an application of the 4th dimension or 4D BIM, otherwise known as the time element. Hence, 4D BIM is 3D BIM + schedule.

What 4D BIM model does is provide an additional dimension of information to a building project. This process comes in the form of scheduling data. As the project progresses, this detailed data is added to the components that are being built. It is even possible to link certain activity bars on your Gantt chart, one of the most popular tools for scheduling tasks, with actual elements of your BIM model, if your BIM software supports it.

What are the benefits of 4D BIM dimension?

  • It helps in planning the building site properly, including the schedule of all the construction stages.
  • Not only does it help in planning, but it also helps to increase the quality of the building site planning.
  • It brings about a good working relationship and cooperation among the stakeholders with clear deadlines.
  • The 4D model is also a great tool to run various testing scenarios, as it allows everyone involved in the project to see how the project would look at different phases of its realization.
  • It reduces disputes and unnecessary delays since schedule-based visualization is an effective way to showcase a team’s specific intentions for each part or phase of a project. With a single project model accessible to everyone, disputes can be resolved more easily, and there is less risk of misinformation and miscommunication.

At the same time, a detailed 4D BIM model would be useful for the entire duration of a construction project’s lifecycle, including:

  • The early concept stage, which centers around a detailed evaluation of whether a project is feasible, can benefit greatly from a 4D BIM model. It provides advantages such as strategic planning, proper space configuration, and detailed analysis of multiple alternatives for a future project, making it easier to pick the most suitable option.
  • During the design detailing stage, a 4D BIM model can help check if the chosen idea can be realized in the real world while looking for the best possible sequence of tasks and operations to bring it to life. It also facilitates sharing project plan details with stakeholders and contractors involved in its realization.
  • In the bidding stage, a 4D BIM model can be helpful in showcasing how a contractor can plan and execute the entire construction process, leading to more accurate and grounded bids. It reduces the risk of miscalculating the project’s scope by providing a better understanding of what needs to be done, including time and resource constraints.
  • During the actual construction process, a 4D BIM model is most useful in improving coordination between different departments, offering a transparent view of how every stakeholder interacts with the project on-site. It allows for regular construction progress reviews, facilitating better progress tracking and comparison of the “as-planned” state of the project with its current “as-built” state.

5D BIM dimension

This is 4D BIM + Estimate or cost. The function of 5D BIM modeling is to integrate cost, schedule, and design in a 3D output. This model is charged with forecasting/predicting the flow of finance for a project and visualizing the progress they have made concerning the project. Visualization brings about the feasibility and unmatched accuracy in any building project.

A major difference between the traditional approach and 5D BIM modeling is the rate at which the project cost is updated and modified. 5D approach means the cost reports can be modified at any given time. This arises as a result of unforeseen circumstances such as a change in design or other modifications.

Additionally, 5D BIM is capable of filling the early design void, allowing all of the parties involved to sit down and calculate both the project design costs at the current moment, as well as how possible revisions can affect the project from different standpoints – since 5D BIM is all about evaluating, be it price, appearance, constructability, schedule, or anything else within the project’s limits.

5D BIM allows every element of your project to be conceptualized and evaluated beforehand, allowing you to make informed decisions with impressive accuracy. The list of benefits that 5D BIM can provide is long and varied and includes, but is not exclusive to, the following:

  • The ability to provide data in real-time allows for a straightforward process of exploring alternative concepts and gives the necessary parties regular updates on project costs and other relevant information, which drastically raises the project’s efficiency.
  • Major project stakeholders can visualize the end product exactly how it will look when finished and see the exact budget estimate with a detailed breakdown – transparency is the key to success.
  • 5D BIM gives a blend of data modeling capabilities that provides a massive boost in predictability over legacy solutions, making it far easier to provide accurate project scope. Each building system in 5D BIM uses many parameters in its calculations, like site conditions, construction materials, phasing, and more.
  • Since the model can recalculate the construction cost each time there’s a model update of any kind, it’s far easier to explore various possibilities with your project.
  • The existence of clear and accurate estimates of various details about the project allows everyone to understand the project and its multiple details thoroughly, be it design, cost drivers, or other factors. Having clear and accurate information about schedules, costs, and the project’s scope eliminates the possibility of a misunderstanding and can become an essential point for funding decisions.

5D BIM is also a perfect fit for the Design-Build approach to projects. With Design-Build, all of the phases of a project are performed by a single entity, from early design to actual construction, which eliminates the need to calculate all of the estimates separately and boosts the overall productivity of a project, in general, since everyone is on the same page from the get-go.

Benefits of 5D BIM dimension

  • Cost Visualization
  • Brings about shorter project cycles.
  • Modification of project cost at any given time
  • Moe easily understood project scope.
  • Helps to alienate any form of budgetary offshoot.

6D BIM dimension

This BIM dimension is also known as iBIM or integrated BIM. 6D BIM involves the addition of other relevant information that supports the facility’ management and operation in the hopes that it will bring about a better business outcome.

The 6D process means that a model that was created by a designer gets updated or modified in the course of the construction. This particular model can be submitted to the owner as an “as-built” model. The model will comprise the necessary information that will be needed in case of any future maintenance. The information includes things such as warranty information, manual information, operation, and maintenance information, etc.

Benefits of 6D BIM dimension

  • It makes decision making very easy and fast.
  • During the project lifecycle, 6D BIM brings about a detailed analysis of the economic and operational aspects of the project.
  • Helps plan for any maintenance phase.

7D BIM dimension

7D BIM basically comprises 3D + time schedule + cost intelligence + sustainability. Builders and project managers alike make use of 7D building information modeling in the maintenance and operation of a project throughout its entire life cycle. Using a 7D CAD in BIM would help optimize the project management from its design stages, up until its demolition.

Warranty information, technical specifications, operation manuals are some of the assets data that can be tracked using this dimension.

Benefits of 7D BIM dimension

  • 7D BIM helps to monitor the management of the facility or asset right from the design stage to the demolition stage.
  • It makes the changing of building parts and general repair of a building/project throughout its entire cycle a very easy task.
  • Pinpoint to the contractor, the maintenance process that must be followed.

8D BIM dimension

8D BIM is one of the least widespread dimensions, with the eighth dimension focusing on health and safety. This topic is of significant importance to the construction industry, which has a long-running reputation for a large percentage of potentially serious accidents that could happen to construction personnel on-site.

Reducing the number of accidents is vital to the industry and every company. 8D BIM is an advanced variation of risk analysis that uses the wealth of information that a BIM model has to predict and analyze every potential problem or accident that could result in human injury. This knowledge is incredibly helpful during the construction phase, allowing workers to know about potential problem locations and be prepared for accidents if the issue cannot be solved beforehand. Risk control can be performed as early as the design stage, and the entire project’s risks can be re-evaluated later to prevent unfortunate accidents for everyone involved in project creation.

As such, we can surmise the advantages of 8D BIM in a single list below:

  • Reduced probability of harmful accidents on-site
  • Preparation of down-to-earth and detailed safety strategies for on-site parts of the construction
  • Better training of the workers with the help of advanced technologies such as virtual reality
  • Easier recognition of every potential design choice that could lead to harmful accidents so that they could be solved as early in the project lifecycle as possible
  • Ability to perform a variety of simulations so that there would be many different scenarios of how the construction process is performed on-site
  • More accurate overview of the state of the construction process, with risk prevention capabilities when it comes to health and safety of the on-site workers


To fully understand a construction project, we must familiarize ourselves with BIM dimensions such as 2D, 3D, 4D, 5D, etc. because these dimensions help to enhance the data of a construction model. Enhancing the data of a construction model will help us know the delivery time of the project, the cost of the project and how to maintain the project.

About the author
James Ocean

BIM/VDC Specialist. James Ocean is Head of BIMspiration at Revizto and keeps everything moving onwards and upwards. From supporting and teaching our internal team as well as our clients, James shows us the ins-and-outs and how to best leverage Revizto to maximize workflows, cut costs, and get all types of projects through the finish line.

Technically Reviewed by Aleksandr Yeghiazaryan
Aleksandr Yeghiazaryan

Aleksandr Yeghiazaryan is the Product Marketing Manager at Revizto, a cloud-based collaboration software platform designed for Building Information Modeling (BIM) collaboration. Founded in 2008, Revizto’s software technologies have been utilized by various organizations, including the City of Barcelona and the Organizing Committee for the XXII Olympic Winter Games.

Alex began his marketing career in 2017 at PUBLIQ, where he was responsible for managing content marketing campaigns globally. In 2021, he joined Revizto as a Marketing Content Leader and was later promoted to the role of BIM/AEC Tech Evangelist. Since 2024, he has been overseeing all of Revizto’s web content, ensuring that it aligns with the latest trends in AEC, complies with local BIM regulations, and more. Notably, Alex is also Revizto Certified, underscoring his expertise in the platform.

Alex is an alumnus of Quantum College, where he earned a degree in Mathematics. He was the winner of the British English Olympics in 2014 and has played a significant role in organizing and participating in six European Youth Parliament events. Besides his professional achievements, Alex is a skilled pianist and occasionally holds concerts.

BIM Dimensions: 2D, 3D, 4D, 5D, 6D, 7D & 8D BIM Most people know the general meaning of BIM, but they don’t know exactly how it works, and what it entails. Hence, the purpose of this post. This post contains all you need to know about the technical workings of BIM, with a focus on BIM dimensions: 2d, 3d, 4d, 5d and 6d BIM. 2024-01-18
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