BIM Level of Development (LOD) Specifications Explained

BIM LOD tells you exactly how detailed your digital building model needs to be at each project stage. Here's what you need to know:

Two key parts make up LOD:

• LOG (Level of Geometry): The 3D visual details
• LOI (Level of Information): The data and specifications

Why this matters to you:

• Cuts building costs by knowing exactly what detail level you need
• Stops teams from doing too much or too little work
• Makes sure everyone works from the same plan
• Helps catch design problems before building starts

Quick fact: Using BIM LOD can cut greenhouse gas emissions by 9-48% in multi-storey buildings.

Want to get it right? Focus on these basics:

1. Match LOD to your project phase
2. Check models before moving up LOD levels
3. Keep your files organized
4. Run regular team reviews

Main Parts of LOD

LOD has two core parts that define your BIM model's detail level:

Visual Requirements (LOG)

LOG (Level of Geometry) controls what you see in your 3D model. Here's what each level includes:

Data Requirements (LOI)

LOI (Level of Information) handles the non-visual data. Here's what you need at each stage:

The AIA says 80-90% of your project elements MUST hit LOD-350 or higher. This means both your model and data need enough detail to build from.

Let's look at an HVAC system at LOD 400:

• Exact duct sizes and paths
• Where it connects to other systems
• How well it performs
• How to install it
• How to maintain it

When LOG and LOI work together, you get a complete picture that shows everyone what to build and how to build it.

LOD Levels Explained

BIM models get more detailed as you move up through LOD levels. Here's what each level includes:

LOD 100: Basic Design

LOD 100 is like a sketch in 3D:

LOD 200: General Design

LOD 200 adds more meat to the bones:

LOD 300: Complete Design

At LOD 300, builders can start their work:

LOD 350: Building Plans

LOD 350 shows how everything fits together:

LOD 400: Building Assembly

LOD 400 tells you how to put it all together:

LOD 500: Final Building State

LOD 500 matches the finished building:

The AIA says most parts of your project need LOD 350 or higher. In other words: your model must be detailed enough that builders won't need to ask "how does this work?"

Using LOD in Projects

BIM teams need specific LOD targets from the start. Here's what works:

Your LOD matrix needs 4 things for each building part:

• The exact LOD level
• Who owns what
• Update schedule
• Quality check points

Project Delivery

Each LOD stage needs these checks:

Here's what makes LOD work:

1. Start with your BIM plan

Map out every LOD requirement in your BIM Execution Plan (BIMXP).

2. Check before you level up

Make sure models hit their LOD marks before moving forward.

3. Track everything

Put LOD tracking right into your project tools.

4. Review as a team

Get everyone together for regular model checks.

The AIA and AGC give you the rules. Their standards show exactly what each stage should look like.

Want better results? Here's how:

• Build detail one step at a time
• Pick LOD levels that fit your needs
• Keep an eye on progress
• Look for system conflicts
• Document your LOD work

Bottom line: LOD isn't about throwing in more detail. It's about having the right info when you need it.

Industry Rules and Standards

Here's what you need to know about LOD standards in BIM for 2024:

BIMForum Guidelines

BIMForum leads LOD standards in US construction. Their 2023 update includes:

ISO 19650 Rules

ISO 19650 connects LOD with global BIM practices through these core areas:

Local Standards

Here's how LOD works in different regions:

Building Code Links

Building codes and LOD connect at each stage:

The AIA and AGC created these standards to boost team efficiency. Each LOD level comes with specific requirements.

"The LOD Specification defines and illustrates characteristics of model elements of different building systems at various Levels of Development." - BIMForum Working Group

For success:

• Stay current with standards
• Match LOD to project needs
• Document your checks
• Follow standard updates

Managing LOD

Here's how to handle LOD tasks without headaches:

Your team needs to share data the right way. Here's what works:

Keep your files in order with these steps:

"Creating search sets and using colour overrides helps teams spot issues faster during constructability reviews", says Dave McCool, Director of Product at Procore.

Here's what to check and when:

"Our Sherlock plugin helps teams find and fix clash issues 60% faster than manual checks", notes Nick Fredricks, CEO of Flypaper.

Want better results? Do these 4 things:

• Run automatic LOD checks with Plannerly's Verify module
• Store ALL files in one spot
• Make file names clear and consistent
• Check your models often

LOD in Action

Here's what LOD looks like at each stage:

Design Stage

At this point, teams focus on two key areas:

Construction Stage

During building, LOD helps you track:

"We cut costs and saved time on our California park project by using a clash-free BIM model with AIA standards", says TrueCADD's project lead.

Building Management

After construction, teams need to know:

Building Care

LOD 500 helps track day-to-day care:

"Using LOD 350, our BIM team delivered a clash-free model on time. This meant less fixes, less waste, and better safety", from Hitech's Australian housing project report.

Problems and Fixes

Here's what goes wrong with LOD - and how to fix it:

Your computer needs to keep up:

Here's what you need for each LOD:

Watch out for these problems:

"The key to being able to break out of this quasi-definition cycle is collaboration." - James Vandezande, AIA, Principal at HOK

What works:

• Look at 2D specs before you import
• Check everything three times
• Stay at LOD 300/350 during design
• Check for clashes after big changes

Remember: LOD 500 is for as-built only - don't aim for it during design.

Tips for Success

Here's what you need to know about setting up and running your BIM project:

Core Documents

You'll need these four key papers:

Quality Checks

Here's what to check and when:

Team Guidelines

Keep these rules in mind:

For your team:

• Double-check each LOD level
• Keep files small and clean
• Use 2D for tiny details
• Build detail levels step by step

For your files:

• Clean up each week
• Link, don't merge
• Back up big changes
• Save old files (30 days)

Remember: ISO says check everything matches specs before moving to higher LOD levels.

What's Next for LOD

The BIM world is changing fast. Let's look at what's coming.

New Tools

The BIM tools market is booming - from £4.1 billion in 2019 to £11.8 billion by 2027. Here's what's shaping up:

Market Changes

BIM is growing 13.7% each year through 2028. Here's what's happening:

Rules Updates

BIMForum's 2023 LOD rules need your input by 15 January 2024. Key changes:

New Uses

LOD keeps finding new jobs:

buildingSMART International continues developing open LOD standards to help BIM tools work together smoothly.

Wrap-up

Let's break down what makes LOD tick in BIM projects.

First up: the basics you need to know.

Here's what makes LOD work in real projects:

Let's talk about what this means for actual building:

"When everyone in the process understands the ground rules, costs can be better managed, and BIM will generate savings." - Benjamin Crosby, Director of BIM for Yates Construction Company

Here's how LOD shapes each project phase:

Since the UK's 2011 BIM mandate, LOD has shown its worth in public projects. Each level does a specific job:

• LOD 100-200: Gets planning and money sorted
• LOD 300-350: Handles permits and deals
• LOD 400: Makes building happen
• LOD 500: Keeps buildings running right

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