The Hidden Cost of Digital Debt: Why Revit Is Only Part of the Solution (Industry Version)

At Kevin Kelly Architects, we’re often asked what design tools we use, especially by those curious about how we move from early concept to detailed delivery. The short answer is that it depends on the stage of the project. And that’s largely because of something few in the industry talk about: the digital debt of Autodesk Revit.

Revit is a reliable and structured tool for co-ordination and delivery. From Stage 4 onwards, we use it to manage complexity, align with consultants, and ensure consistency across drawings and specifications. It plays an important role. But assuming it can support the full arc of a project, from first sketch to final fixings, is where we often see issues arise.

There’s a common misconception that BIM and Revit are the same thing. In reality, BIM is a strategic process. Revit is just one tool within it. While Revit handles standardised components well, it struggles when the work is more exploratory, layered or expressive.

This is where digital debt becomes visible. Revit was built over 20 years ago. Although it has evolved, its underlying structure hasn’t fundamentally changed. It was never designed for fluid modelling or early-stage design thinking. Its engine is rule-based. Its modelling behaviour is often rigid. It’s very good at documenting decisions, but less helpful in making them.

This limitation is, in part, due to Revit’s core logic: a solids-based system derived from the ACIS kernel, which prioritises stability, precision, and parametric clarity over geometric freedom. Compare this to mesh modelling, used in platforms like Blender or Maya, where form is manipulated as a flexible skin made of interconnected vertices and faces, ideal for sculpture or animation. Then there’s NURBS-based modelling, such as Rhino, which offers mathematically precise control over curves and surfaces, allowing for more fluid, intuitive exploration. Voxel-based modelling, while less common in architecture, offers a pixel-like approach to 3D form, ideal for certain kinds of computational experimentation.

Beyond these, data-driven approaches, like scripting in Python or using visual programming languages (VPLs) such as Grasshopper, allow for parametric design that’s responsive, iterative, and often generative. These systems don’t just model geometry; they define relationships, behaviours, and rules. For early-stage concept design, this opens up far more creative possibility than a fixed library of walls and windows ever could.

At KKA, we use these tools to stay agile and responsive. Our mixed approach allows us to test, tweak and evolve designs quickly, something that’s especially valuable in early-stage conversations. It also allows our small team to be highly productive, delivering a lot with lean resources. When we coordinate with collaborators, consultants, clients or contractors, we provide the right kind of information at the right time. There’s little point explaining Python to most clients, and we don’t, but we might use that same script to quickly generate a clear, elegant visual that helps them make a decision with confidence.

We would be lying if we said we haven’t seen design diluted from time to time due to tools being misused. Our tools shape our thinking, and our thinking informs how we use our tools. The more skilled and flexible we are across a wide spectrum of design platforms, the more value we bring to clients, collaborators and contractors alike. Imagine a builder trying to do everything with just a hammer, they’d be digging foundations for a very long time.

We don’t believe moving 2D lines and points around a screen is good value for clients. What matters is clarity. Whether we’re developing a design or communicating it, our tools are there to support a shared understanding.

So at KKA, we use the right tool at the right moment. For the early stages of a project (RIBA 1 to 3), we design with flexibility, using Rhino, Grasshopper, sketching, physical models, or whatever suits the project best. Then, from Stage 4 onwards, we transition into Revit for delivery.

Sometimes we incorporate unique design elements into Revit using custom families or adaptive components. Other times we place simplified placeholders into the model, supported by direct-to-fabrication geometry or external references.

What matters to us is that our ideas remain intact, and that our clients feel that integrity right through to completion. Creativity is where our value begins, but delivery is where that value is realised. Revit helps us with the latter, but we don't let it restrict the former.