12d is one of those tools that people tend to have a strong opinion about. Some pick it up quickly and see the value straight away. Others find it clunky and hard to work with. I’ve seen both sides of that over the years I’ve been working in the industry.
At Marvel Engineers, we’ve built a lot of our workflow around it. When it’s used properly, it gives us a level of control over our design that’s hard to get elsewhere. So instead of getting into what 12d is, this is more about how we actually use it and where it makes a difference on our projects.
Why we’ve ended up using 12d the way we do
There are plenty of design platforms out there, and we’ve used a few over the years. We kept coming back to 12d because it suits the way Marvel works. The biggest advantage for us is continuity. It lets us take a job from survey through to detailed design and into construction outputs without constantly rebuilding or translating data between systems.
When everything sits off the same model, you’re not second-guessing which version is right or trying to reconcile differences between stages. It just removes a lot of friction, and that consistency carries through the entire project.
When everything lines up
When you’ve got good survey data and a clear scope, 12d works really well. You can build the model, test different options, refine it, and carry that through to construction outputs without too much rework. The model behaves as expected and the process is relatively straightforward.
That’s the ideal scenario, but it’s not how most projects start.
Where things get tested
In practice, the biggest challenges usually come back to inputs and speed.
If your survey isn’t right, the model won’t be either. You can usually pick it up pretty quickly. Things don’t quite tie in, levels feel off, edges do not behave how you expect. You can work through those issues, but it slows everything down and introduces risk if it’s not picked up early.
The other risk is speed. Once you’re comfortable in 12d, it’s easy to move quickly and produce outputs with relatively little effort. But speed can work against you if you’re not careful. Just because something runs doesn’t mean it’s correct.
We’re deliberate about stopping to check what the model is actually doing and whether it reflects the design intent. That discipline makes a big difference to the quality of what goes out the door.
Where we see the most value from 12d
For us, the biggest benefit comes from iteration. As we all know, design is rarely right the first time. Being able to adjust things, test options, and keep building on the same model makes a big difference and is where 12d really adds value.
Whether it is earthworks, layouts, or trying to make an alignment work within geometric constraints, it allows us to build on the same model as the design evolves, rather than constantly recreating information. That doesn’t just improve efficiency, it leads to better design outcomes because more options can be properly explored.
Thinking beyond the design
Our main focus is what happens once the design leaves our hands. A model can look complete on screen and still create issues during construction if it hasn’t been thought through properly. That’s where a lot of projects come undone.
We use 12d to:
- produce construction-ready models
- set-out information
- create outputs that contractors can pick up and use immediately.
The less interpretation required on site, the better. If someone has to guess what we meant, we haven’t finished the job properly!
Getting the team aligned
This approach only works if the whole team is aligned. We’ve put a simple structure around how we build and manage models so that anyone can step into a project and understand what’s going on.
It’s not overly complicated, but it provides enough consistency to avoid confusion and reduce rework. Without that structure, models tend to drift and small inefficiencies start to compound.
Working within 12d Synergy
One thing that has made a noticeable difference for us is using 12d alongside 12d Synergy as our Common Data Environment (CDE). It keeps everything connected in a way that suits how 12d works. Models, data, and changes are all managed in one place without having to move files back and forth between different systems.
What that really helps with is control, so you’re not wondering who has the latest version or whether something has been updated somewhere else. It is all tracked and visible.
It also makes collaboration easier with multiple people working on the same job without stepping on each other. And you spend less time managing files and more time doing the work.
It is not something you notice straight away, but over the life of a project it makes things run a lot more smoothly.
Meeting client requirements
A lot of our work is with clients like Queensland Department of Transport and Main Roads (TMR), where the outputs are clearly defined and there is not much room for interpretation.
That brings a different level of discipline to how we set things up in 12d. We’re not just producing a design that works. We’re producing something that must meet specific requirements around models, strings, surfaces, and how everything is structured and delivered.
What 12d does well here is give you the control to align with those requirements from the start, rather than trying to bolt it on at the end. We build our models with those outputs in mind, so when it comes time to deliver, it’s not a separate task. It is just part of the process.
The jobs that run well are the ones set up properly early. The ones that struggle are usually trying to pull outputs together at the end.
Conclusion
12d isn’t doing anything magical for us. What it gives us is a consistent way to build, check, and refine designs, and then carry that through into construction.
Like any tool, you can get caught out if you rely on it too much without thinking things through. Used properly, it helps us deliver designs that hold together not just in the model, but on site as well. And that’s really the point.
If you want to talk through how we are using it, or where it might fit on a project, feel free to reach out.
Read more about Marvel’s work in the information management space in our articles BIM demystified: Making sense of the acronym and BIM and ISO19650: The nuance of naming.