LOD 200 or LOD 300 — how much detail does your BIM model actually need?
Level of Development decides what a BIM model contains, what it costs, and what you can legitimately do with it. Specify too low and the model cannot carry your design. Specify too high and you pay for detail nobody will use. The gap between LOD 200 and LOD 300 is where most as-built briefs are won or lost, and the difference is easier to see than to describe.
The short version
- LOD 200 gives approximate geometry: elements are present, sized roughly, positioned roughly.
- LOD 300 gives measured geometry: real dimensions, real positions, real profiles.
- LOD 200 suits feasibility, concept design and area calculations.
- LOD 300 is required for technical design, joinery and anything fabricated to fit.
- The step from one to the other typically adds 30 to 50 % to the modelling time.
Side by side
| Criterion | LOD 200The element exists, roughly where and roughly what size. | LOD 300The element as measured, with its real dimensions and profile. |
|---|---|---|
| Geometry | Generic, approximate size and position | Measured, real size and position |
| Walls | Correct thickness, position within a few centimetres | Measured thickness, position to a few millimetres, out-of-plumb recorded |
| Openings | Present, roughly sized | Measured width, height and reveal, with the frame profile |
| Mouldings and profiles | Not modelled | Modelled with their real section |
| Floor levels | One level per storey | Real variations recorded, including falls and steps |
| Suitable for | Feasibility, concept design, area schedules | Technical design, fabrication, made-to-measure joinery |
| Relative cost | Baseline | 30 to 50 % more modelling time |
LOD 200 is enough when
- You are testing feasibility and need volumes rather than millimetres
- The brief is area schedules, ratios or massing
- The building will be substantially demolished or rebuilt anyway
- You are at concept stage and the design will move considerably
- The budget matters more than the last centimetre
LOD 300 is required when
- Joinery or fittings will be manufactured to the model's dimensions
- You are matching existing mouldings, cornices or profiles
- Aluminium or steel glazing is being fabricated off site to fit an opening
- Services are being routed against measured soffits and voids
- The technical design package will be tendered from the model
What we would do
Specify the level your next stage needs, not the level that sounds thorough. A model can be taken from LOD 200 to LOD 300 later on the parts that turn out to matter, which is usually cheaper than modelling an entire building to a level only three rooms will use. What is rarely recoverable is the opposite: a survey captured too coarsely cannot be refined without going back on site.
Common questions
What is the practical difference between LOD 200 and LOD 300?
At LOD 200 the model tells you an element exists, roughly where and roughly what size. At LOD 300 it tells you what was measured: real dimensions, real position, real profile, and the ways the building is out of square. On a period window, LOD 200 gives you an opening; LOD 300 gives you the archivolt, the frame section, the projecting sill and the shutters.
Which level do I need for a planning submission?
LOD 200 is generally sufficient. A planning file needs accurate areas, volumes and elevations, not fabrication detail. LOD 300 becomes necessary at technical design, when things start being made to fit.
How much more does LOD 300 cost?
Typically 30 to 50 % more modelling time, because every element has to be measured against the point cloud rather than placed generically. On a heritage building with mouldings and non-orthogonal fabric, the gap is at the top of that range.
Can I upgrade from LOD 200 to LOD 300 later?
Yes, provided the original scan was dense enough — which is why we keep the registered point cloud with the model. The refinement is done on the parts that matter, without returning to site. The reverse is not true: a survey captured too coarsely cannot be refined at all.
Do you deliver LOD 400?
Not on as-built surveys, and no honest bureau should claim to. LOD 400 describes fabrication and assembly detail, which comes from the manufacturer's shop drawings, not from measuring an existing building. What a scan can legitimately reach on existing fabric is LOD 300.
Which level should I write into the brief?
Write the level and the reason. « LOD 300 on the facades because the glazing is being fabricated off site, LOD 200 elsewhere » is a brief a bureau can price accurately and you can hold them to. A brief that just says « LOD 300 » across a whole building usually buys detail nobody opens.