Construction · Building physics · 5 years
Bunch Bygningsfysik
Five years and counting on a web UI for a proven building physics engine.
Ongoing development since 2021 for a Danish building physics consultancy. I built their moisture content calculator for construction compositions, keeping the existing calculation module with years of expertise baked in as the engine and putting a modern, easy to use web UI on top, and I have kept developing and maintaining it since.
At a glance
- Full-Stack Developer
- Freelance
- 5 years
- TypeScript · React · Next.js · Tailwind CSS · Node.js · MySQL · Vercel · Legacy calculation engine
Context
The company and the situation
Bunch Bygningsfysik is a Danish building physics consultancy. They had a calculation module for moisture content in construction compositions with years of expertise baked into it. The logic was trusted. The way people had to use it was not. I came in in 2021 and have been their developer since.
The brief
What they needed
Make the calculator usable by customers and colleagues through a modern web application, without risking the correctness of the calculations, and then keep it moving as their needs and their customers' needs changed. The obvious shortcut, rewriting everything from scratch, would have thrown away the most valuable part.
What I did
What I built and did
A web-based moisture content calculator for construction compositions, used through app.matchlab.io.
Kept the existing, proven calculation module as the engine instead of rewriting it.
A clean input flow for compositions, materials and parameters, with results that update as you work.
Validation, clear presentation of results and the plumbing between the new UI and the legacy engine.
Ongoing development and maintenance since 2021: new features, upgrades and fixes as the tool and its users have grown.
How we worked
The shape of the engagement
It started as a clearly scoped build and turned into a long-term engagement. We agreed on the goal first: better access to the calculator, not a new calculator. I treated the existing module as a black box with a contract, wrapped it, and spent the effort on the interface and the edge cases users would hit. Short iterations and early demos meant the building physics experts could correct me before anything was expensive to change, and that rhythm has continued through years of further development.
Outcome
What it led to
The calculator is live, in use and still evolving, and the expertise in the original module is intact. Five years on, Bunch Bygningsfysik is one of my longest engagements. It is the clearest example of a principle I follow everywhere: keep what works, modernise what does not, and do not confuse the two.
Building something in the same space?
Tell me what it is, roughly when it needs to exist, and what a great result looks like. I usually reply within a day, and the first 30-minute call is free.