If you've worked on both US-influenced and ISO 19650-aligned projects, you've probably noticed the same underlying question — "how detailed does this element need to be at this stage" — gets answered with two different vocabularies. Knowing both, and why the shift is happening, matters increasingly for anyone working across Indian projects with international clients.
LOD: geometry-first, US-influenced
Level of Development (sometimes Level of Detail) describes how complete and reliable a model element is at a given project stage, most commonly using the BIMForum LOD specification scale — LOD 100 (conceptual) through LOD 500 (as-built/verified). LOD is primarily a geometric and reliability concept: how much can you trust this element's shape, size, and location at this stage.
LOIN: information-first, ISO 19650-aligned
Level of Information Need is the ISO 19650 term, and it deliberately covers more ground than LOD — both the geometric detail AND the non-geometric data (specifications, performance data, classification codes) an element needs to carry at a given stage, for a given purpose. The "for a given purpose" part is the key shift: LOIN asks not just "how detailed is the geometry" but "what does this specific information need to support" — a cost estimate, a clash check, a facility management handover — each of which might require different data, not just different geometric detail.
Side-by-side comparison
| Aspect | LOD | LOIN |
|---|---|---|
| Primary focus | Geometric detail and reliability | Geometric AND non-geometric information, tied to purpose |
| Origin | BIMForum (US), AIA E202 | ISO 19650 series (international) |
| Typical scale | LOD 100–500 | Defined per use case, not a single fixed numeric scale |
| Where it's expected | US, US-influenced, and many global private projects | UK, EU, and increasingly Indian government/ISO-aligned projects |
Why India is shifting toward LOIN
As Indian government and large infrastructure projects increasingly require ISO 19650-aligned delivery — driven by central mandates above ₹500 crore and state-level adoption in Maharashtra, Karnataka, and Tamil Nadu — the contractual and guideline language is shifting to match. An EIR written under ISO 19650 principles will typically specify information needs using LOIN-style thinking, even if the term "LOD" still appears informally in day-to-day team conversation out of habit.
What this means practically for your work
In practice, most experienced BIM professionals end up bilingual on this — using LOD shorthand informally with colleagues while understanding that any formal EIR or BEP/IPP documentation on an ISO 19650 project should be specifying information need by purpose, not just a geometric detail number. If you're authoring an EIR (see our EIR writing guide), specify what each piece of information is actually needed for — cost planning, clash detection, FM handover — rather than defaulting to a single LOD number applied uniformly.
LOD/LOIN distinctions and how to specify them correctly in project documentation are covered in our Apex plan, alongside hands-on EIR and BEP/IPP authoring practice. Full curriculum on the Programs page.
Frequently asked questions
What does LOIN stand for in BIM?
LOIN stands for Level of Information Need — the ISO 19650-aligned term covering both geometric and non-geometric information requirements, replacing the more geometry-focused LOD.
Is LOD still used in BIM projects?
Yes, LOD remains widely used, especially in US-influenced projects, while ISO 19650-aligned projects are shifting toward LOIN terminology.
