We make residential projects simple.
Renaldo is a software and training company based in Hamburg, Germany.
Experience, turned into a tool.
We first met back in 2019 at ecoworks. In October 2023 a LinkedIn post by Ronald about his “retrofit sprint” in Hamburg-Duvenstedt was the trigger: Gregor picked up the phone, the planned quick call turned into an hour — and just before Christmas, on 21 December 2023, we founded Renaldo together.
The goal from day one: make retrofitting single-family homes in Germany simpler, faster, safer and cheaper — first with the retrofit sprint, then with the Renaldo app. That way we want to help thousands of homeowners and retrofit coaches deliver successful projects, and to contribute against climate change by speeding up energy efficiency and the switch to low-carbon heating.
Rethinking residential buildings.
Retrofitting in Germany has to become faster, fairer and more transparent — and that only works when homeowners, professionals and lenders speak the same language.
Renaldo is what holds it together. One data room, one AI, three worlds. Not a tool built to impress — one built to save hours.
Our guiding principle: think about a retrofit from the end backwards.
Cost certainty first, then the plan — because every contractor invoice ultimately comes down to work item × quantity × unit price. Those are exactly the three figures Renaldo makes reliable from the very start.
We renovated first, then built the tool.
Renaldo founded
A few weeks after Ronald's sprint in Hamburg-Duvenstedt, the decision was made on 21 December.
As a general contractor
Three retrofit sprints run in-house — twice in Hamburg, once in Markkleeberg near Leipzig.
As a digital design practice
Numerous retrofit projects and sprints supported through design and delivery.
As a software & training company
Experience and data feed the app and the courses — knowledge and tooling for retrofit coaching.
Four principles we want to be judged by.
Tools that save hours.
Not features that impress — features people actually touch.
Transparent pricing.
No small print, no lock-in contracts, cancel monthly.
Taking GDPR seriously.
Hosted in Germany, no trackers, no data passed on to third parties.
Built with real clients.
Every feature is tested with people doing the work before it goes live.
Two founders, one mission.
Gregor Loukidis
Impact founder and unapologetic tech enthusiast.
Ronald Meyer
More than 30 years of retrofit experience.
Hamburg is home.
A Hanseatic city with a long view: trades, design and entrepreneurial drive all meet here — and projects like yours grow in between. We work out of Hamburg-Sasel, quiet and green in the north of the city, a short hop from sites and partners across the metropolitan region. Weather, water and plenty of room to think — which suits retrofitting rather well: matter-of-fact, down to earth, quality over frills.