What Is a LOD

What is a LOD – Level of Development? Why it’s so important to choose the right one?

In the BIM industry, a lot of people are not aware of what exactly LOD (Level of Development) is. This is a very frequent question and many people have debated the topic. In this post, we will introduce you to the meaning of LOD. You will learn how to use it and why it is so an important part of BIM.
 
Before we dive into these details, we need to answer the question, “Why do we need to decide on a certain Level of Development?”. The fast answer would be to make things easier.
 
Let’s say we have a client who needs to provide us with information and details about the project. Before we took the real references, for instance, from the BIM Forum. The client had to load and go through all the 250 pages of documentation. The problem here is that nobody has the time and wants to spend the effort of going through all the papers. It’s too much. Additionally, this amount of information could be very confusing to the client. Usually, he wants something particular. So, he would refuse to go through all the paperwork to give us a clarification of what exactly he needs and wants from us.
 
Occurred a need to have all the information from those 250 pages simplified. So, it is easier and quicker to understand. As a result, we are presenting well-structured information. That helps him to point out what his actual desire is. He could go through the document, see the images, and understand what he will get.

LOD

 

So, what is LOD (Level of Development)?

 

LOD (Level of Development) is an individual component in the BIM model that has particular information. It could be graphical, non-graphical, or documentation. This is very helpful when you build a digital model, depending on the phase you are at or depending on your needs.

For example, if the client needs a graphical representation of the building or the construction model only. This way the digital information would be correct. It will be designed correctly in the digital environment. From there, the Contractor can easily direct and copy it. That’s why the document is so essential.

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There are various explanations for what LOD (Level of Development) is. Many companies interpret the concept in their own way. Marzia Bolpagni has published a diagram (LoX) (in Politecnico di Milano)*. It represents how many organizations have released different information, explanations, and interpretations about LOD. There are a lot of different and non-consistent opinions on the concept. There isn’t one document that explains what is LOD. The diversity of heterogeneous information, coming from various sources, could be extremely confusing. Each country has its own understanding and interpretation of LOD.

LOD (Level of Development)
Marzia Bolpagni in Politecnico di Milano

Do you want to learn more about LOD (Level of Development)? Watch the video Level of Information Need | BIM TALK with Marzia Bolpagni

And if this is not confusing enough, wait to hear this. There is a document in BIM “ISO 19650” in which the name of LOD is changed to LOIN (Level of Information Needed). So it could fit their own standard.
 
Maybe, after time, the concept will be settled down. Eventually, it would bring equal meaning and value to anybody in the industry. But for now, the different professionals and organizations refer to different meanings.

ISO 19650

At the end of the day, it doesn’t matter who and how LOD is interpreted. But what value does it give to the client and how he (the client) evaluates it? Is it helpful enough? Are they able to easily understand what they need from that document?

Responsibility Matrix

 
There is another level of LOD documentation—the responsibility of the matrix. It highlights, at which stage, and who handles a particular level of information.
 
For example, the resources that could be tackled the color and the color at this stage have to be LOD 200. But the next stage should be LOD 300. So, it needs to be distributed properly.
 
This could be very difficult because there are lots of components in the model. It’s hard to decide at which stage what information we really need. Yet, we still need to have the information in place. Because in the BIM execution plan we have to know when we are going to get a particular element, and at what level of detail. This is the way we are ensuring that the project will run smoothly.
 

Is the size of the project important for using LOD (Level of Development)?

 

No, the project scale does not really matter for the LOD (Level of Development) because LOD could be applied to every project. There are other factors that we have to pay attention to through the BIM workflow.