With the advancement in the tech world, where every department is making advanced progress by using technical software, the AEC (Architecture, Engineering, and Construction) industry is no exception in this regard. The latest revolution in the AEC world is BIM (Building Information Modeling), which is a digital framework that assists with creating, managing, and sharing detailed information about your building projects. Gone are the days when you have to rely on hand drawings of your project as advancement in BIM has completely revolutionized the AEC world.

Although Building Information Modeling (BIM) is itself a significant transition, nevertheless LOD (Level of Development/Details) and LOI (Level of Information) have exceeded the BIM services beyond the standard approach. Nowadays, BIM is offering a whole package filled with a multidimensional approach ready to enhance its efficacy with visual representation, collaboration, and data integration. Unlike 2D drawings, LOD and LOI offer data-rich information that enhances the visualization, analysis, and optimization of your building project from every aspect. Here in this blog, we will understand how LOD and LOI help the stakeholders leverage BIM’s full potential and navigate the complexities of modern construction with confidence.

Understanding the basics of LOD and LOI

The efficacy of Building Information Modeling lies in two pillars, BIM LOD and BIM LOI. On combining these two technologies, stakeholders craft an integrated 3D model of your building. Both pillars work in different ways, yet complete the information. LOD offers geometric precision such as the size and dimension of walls, doors, etc, while LOI refers to the data information attached to the model of your building. Together these two key elements ensure that the BIM model of your building would be visually accurate while enriching the information with all action-able data.

Both LOD and LOI are divided into certain levels that help in ensuring the level of BIM design. At the start of drafting a design, a low LOD 100 is assigned that contains the basic and conceptual development of the BIM model. However, the final BIM design contains Higher LOD (400-500) for construction documentation and fabrication. Meanwhile, the level of LOI indicates information regarding the material specification, cost, and performance data. Both LOD and LOI work side by side in any BIM design to assist the stakeholders with streamlined workflows, minimize rework, and deliver projects.

Exploring BIM LOD (level of Development)

The term BIM LOD entertains two phrases, Level of Detail and Level of Development. Talking about Level of Detail refers to the details of the models, including the number and size of primitives used in them. However, the level of development (LOD) brief indicates to what extent the design has been completed. LOD is a worldwide recognized standard used to determine the level of detail and accuracy at different stages of BIM development. LOD ensures fair communication between project stakeholders and briefs about the phases of construction. It also prevents misunderstandings and discrepancies while executing the construction. Moreover, it assists the management of expectations regarding the quality of work and the maturity of BIM data.

The AIA (American Institute of Architects) has developed a standard framework for LOD levels. LOD is divided into six different levels, starting with conceptual development to the full building design. Each level includes specific details and information.

LOD 100 (conceptual design):

This level is the most basic and helps to understand the conceptual idea of the building. It includes minimal geometric details by using symbols and generic shapes. For example, representing the basic structure of a building using simple blocks. It will brief you about the approximate dimensions. It briefs about the early-stage design and also provides the cost estimation of your project.

LOD 200 (Schematic design):

It includes a generalized schematic design that includes minimal geometric detail by using symbols and generic shapes. It is considered an early-stage development that offers feasible studies as well as cost estimation. For example, A design of a building that includes the walls, roofs, and floors with approximate dimensions and general shapes.

LOD 300 (Detailed Design):

This level is advanced and offers accuracy and a good representation of components. Also brief about their dimensions, shapes, and location. It also interlinks the specific materials and creates a connection between them. For example, a proper showcasing of walls with exact dimensions, material specifications, and connections to the elements.

LOD 350 (Construction documentation)

It includes the detailed geometry and the connection of the building with other buildings. It detects any clashes in the system. For example, take it as a duct system designed with the proper dimensions and its connection to the walls and ceilings.

LOD 400 (Fabrication and assembly)

It showcases highly detailed models that are perfectly suited for fabrication and assembly. It offers precise fabrication details like shop drawings and assembly instructions. For example, A steel beam includes exact bolt patterns, welds, and connection details.  It assists in manufacturing as well as construction.

LOD 500 (As built/ facility management)

It represents the final construction of your building, including all the installed components and actual field measurements in it. This level contains the fully verified geometry and data. Take it as an example of a complete building having all the installed systems, types of equipment, and finishes.

Understanding the levels of development means acknowledging the geometric details and reliability of a BIM model. It makes sure that the stakeholders should have a clear understanding of the system and its accuracy at every stage of development. Besides, it also assists in collaboration between the design and construction teams.

Exploring the BIM LOI model

Talking about LOI, it directly relates to the data and information associated with your BIM model. In contrast to LOD which focuses on geometric details, LOI focuses on those non-geometric details that focus on the context as well as the meaning of the model. It comes with the two main types of information;

Geometric information comprises dimensions, shapes, and locations of building elements such as the exact height of the wall, its width, and the position of the building. Meanwhile, the non-geometric data focuses on materials, costs, performance data, and maintenance schedule of your building, such as the door’s fire rating, installation instructions, and hardware details.

Both LOI and LOD work side by side to complete an ideal BIM model for a building. LOI briefs about data richness of the model making it more worthy for project management as well as decision making.

Suppose a BIM model has 300 LOD and also comes with a high level of LOI, it means that the model is complete both in terms of visualization and actionable information.

Take an example of a window in a BIM model. Practicing LOI means getting geometric information (like size, shape, and location) as well as non-geometric information (material type, U-value for energy efficiency, and maintenance requirements).

Both the LOD and LOI models in BIM assist in design, construction, and facility management, ensuring that projects are completed efficiently and effectively.

Relationship between LOD and LOI

Consider the Level of Development and Level of Information as the two sides of the same coin. LOD offers perfect geometric detail and reliability, while LOI focuses on data and information associated with the model’s element. Working together both LOD and LOI ensure visually accurate and actionable data, resulting in a comprehensive BIM model that allows you to make accurate decisions throughout a project’s lifecycle.

Information	LOD	LOI
Focus	Geometric detail and reliability of the BIM model.	Data and information attached to the model’s elements
Definition	Defines the level of detail in the model’s geometry	Defines the amount and type of data in the model
Examples	Shapes, dimensions, connections	Material specifications, costs, performance data
Purpose	Check the accuracy and precision of the model	Ensure the model is rich with actionable data
Impact	Reduce the geometric errors during construction	Features about decision making, cost, and maintenance of the building
Practicality	A wall at LOD 300 includes exact dimensions and layers	A door includes data like fire rating and hardware details.

 

The table acknowledges that in successful BIM projects both LOD and LOI work side by side for effective results. The absence of either LOD or LOI leads to errors and reworking. For example, without LOD the model lacks the necessary geometrical precision for construction and coordination, meanwhile, lack of proper LOI in the model means insufficient data required for decision-making, costing, and facility management. Together they feature the holistic view of one’s project.

For a better understanding, take an example of the design phase of a building. A Low LOD (100) provides conceptual discussions about the project, however, the basic LOI data tells us about the building’s purpose and its size. As soon as the project progresses to the construction phase, LOD gradually increases to the higher (300 or 400) levels offering a detailed geometry BIM Level of Development (LOD) and Level of Information (LOI)

and precise connections while the LOI expands to include material specifications, costs, and installation instructions. Finally, the LOD approaches the 500 level reflecting the as-built condition and the LOI expands to the maintenance, energy performance data, schedule, and warranty information.

Standards for LOD and LOI

LOD and LOI work on consistency, clarity, and interoperability while providing an accurate BIM model that fulfills industry standards. To ensure the precision LOD and LOI in BIM fulfils the following industry standards and guidelines. These are mainly designed to entertain clear communication among stakeholders, reducing misunderstandings across the project. Let’s have a sneak peek at key standards for LOD and LOI;

AIA E202 (American Institute of Architects)

The most widely recognized document for LOD in the United States. It includes the six levels of development starting from 100 to 500. And provides the essential geometric and non-geometric details. This standard ensures that all the stakeholders, including engineers, architects, contractors, and owners, have a clear understanding of the model’s reliability.

UK BIM Framework

This standard provides an understanding of both LOD and LOI. In the UK LOD is referred to as the level of detail, meanwhile LOI means the level of information.  Both LOI and LOD create a framework that works together and ensures that the right information is available at the right time.

ISO 19650 (International Standards)

The ISO 19650 series is the global standard for BIM, providing guidelines for managing information throughout the lifecycle of a building or infrastructure asset. It emphasizes the importance of defining and managing LOD and LOI to ensure consistency and interoperability across international projects. ISO 19650 also highlights the role of information management in achieving project goals, such as cost savings, improved collaboration, and sustainability.

Adhering to these standards is crucial as they provide consistency, interoperability, and efficiency that assist the stakeholders in understanding the LOD and LOI while sharing the models across different software platforms and teams. Also, it provides the standard streamlined workflows, which save much time and cost. Moreover, it assures that the model will meet the required level of detail and information, improving overall project quality.

Final thoughts:

While working on any BIM model, the Level of Development and the Level of Information are foundational concepts. Their primary goal is to entertain your project with the reliability, accuracy, and usability of digital models throughout the lifecycle of your project. Both LOD and LOI work side by side as the comprehensive tool for ensuring proper decision-making, collaboration, and project management. For industry professionals, adopting LOD and LOI standards is no longer optional, it’s a necessity. By leveraging these tools, you can stay ahead in a competitive market and deliver projects that meet the highest standards of quality and innovation.