The Myth of LOD: Why Level of Detail Is Misunderstood in BIM Projects?

By Roots BIM LLC | BIM Perspectives | July 2025

In the world of Building Information Modeling (BIM), few acronyms stir as much confusion—and misplaced confidence—as LOD.

Ask ten professionals what Level of Detail (or Level of Development) means, and you’ll likely get ten different answers, ranging from vague references to “how detailed the model looks” to rigid numeric levels misunderstood as project milestones.

It’s time to bust the myth: LOD is not about the quantity of detail—but the quality of reliability. Let’s dig deeper into how this misinterpretation creates bottlenecks in BIM workflows—and how to get it right.

🧱 LOD: A Quick Recap

The Level of Development (LOD) framework was formalized by the American Institute of Architects (AIA) and further refined by the BIMForum. It outlines how much and what kind of information a BIM element contains at various stages:

• LOD 100 – Conceptual: Massing model only, used for early design intent
• LOD 200 – Approximate geometry: Generic placeholders with assumed data
• LOD 300 – Accurate geometry: Dimensionally correct elements for coordination
• LOD 350 – Interface-ready: Includes supports, connections, or penetrations
• LOD 400 – Fabrication-ready: Includes fabrication, assembly, and installation details
• LOD 500 – As-built: Verified field data post-construction

🧠 The Misunderstanding: Detail ≠ Development

The most common mistake? Equating LOD with visual detail.

Many project stakeholders, especially clients or non-BIM professionals, assume:

“LOD 400 must mean a hyper-realistic, fully textured 3D model.”

But in truth, LOD is not about visual fidelity—it’s about informational maturity and decision-making reliability. For example:

• A pipe at LOD 300 might look the same as one at LOD 400, but only the latter has manufacturing specs and installation constraints embedded.
• An HVAC diffuser modeled at LOD 200 might be fine for clash detection, but not reliable for procurement or costing.

🧩 The Domino Effect of Misinterpreting LOD

Misunderstanding LOD has ripple effects across BIM projects:

1. 🚧 Over-modeling Wastes Time

Modelers push for high LODs early—adding unnecessary details too soon, inflating file sizes, and slowing down coordination platforms.

2. 💸 Cost Overruns and Budget Mismatch

Clients may assume a model labeled “LOD 350” is ready for procurement—but without embedded manufacturer specs or tolerances, the model is useless for estimation.

3. 📅 Scheduling Discrepancies

Construction schedules tied to inaccurate LOD assumptions lead to rework, delays, and trust breakdowns between stakeholders.

⚙️ LOD vs. LOI vs. LOA: The Alphabet Soup

Another myth? That LOD is all you need. In fact, three dimensions must be considered:

• LOD (Level of Detail/Development) – The geometric and informational accuracy of the element
• LOI (Level of Information) – The non-graphical data attached (e.g., manufacturer, warranty)
• LOA (Level of Accuracy) – How true the model is to reality, especially for scanned or existing assets

Many global standards, including ISO 19650 and BS 1192, now recommend a separation of geometry and information, urging a more modular and purpose-driven approach to modeling maturity.

🛠️ So, What’s the Fix?

✅ 1. Define the LOD Matrix Clearly

Each project should start with a BIM Execution Plan (BEP) that clearly defines what LOD levels mean for each element—and when they are needed. Avoid relying solely on LOD numbers. Use Element Development Matrices that outline expectations in plain language.

✅ 2. Educate Stakeholders

Conduct workshops or onboarding sessions with clients, designers, and contractors to clarify what LOD really means and why over-detailing early is harmful.

✅ 3. Align LOD with Use Cases

Tie model development to real use cases:

• Need for quantity take-off? Ensure LOD and LOI are sufficient for that.
• Preparing for fabrication? Shift to LOD 400, but only for the relevant elements.

✅ 4. Embrace Progressive Detailing

Let go of the idea that the model must be “complete” early. BIM is iterative. Embrace just-in-time detailing, where elements evolve in parallel with decision-making stages.

📣 Final Word: Let’s Evolve Beyond the Numbers

The myth of LOD has stuck around because it's convenient—but misleading. Instead of fixating on numeric thresholds, BIM maturity should be driven by purpose, not polish.

As we push toward more collaborative, connected, and data-rich digital construction environments, clarity in communication—and maturity in expectations—will be the real foundation for success.

Let’s stop building myths. Let’s start building smarter.

At Roots BIM LLC, we don’t just model—we deliver clarity, coordination, and construction-ready intelligence.

If you're ready to eliminate confusion around LOD, streamline your BIM workflows, and unlock true project efficiency—

📞 Let’s build smarter together.

👉 Visit www.rootsbim.com or contact us at +1 440 836 3376 or, info@rootsbim.com to elevate your next BIM project.

Related Reads:

• 📘 ISO 19650 Explained: A Practical Guide to BIM Implementation
• 📊 Creating a Purpose-Driven BIM Execution Plan (BEP)
• 🛠️ The Real Difference Between LOD 300 and LOD 400 in MEP Coordination