CARLO Design is an architecture and interior design studio in Berlin Mitte. We plan conversions, Altbau renovations, extensions and new builds across Berlin, establish in advance what can be approved, and file the Bauantrag, the building permit application, under our own permit signature. We work through HOAI work stages 1 to 9 and stay on site until handover.
Charlotte Wiessner founded CARLO Design as an architect in Berlin in 2015. Since then the studio has completed more than 40 projects; in Berlin they are mostly Altbau apartments, but also houses, offices and a restaurant on Kurfürstendamm. The studio on Christinenstraße is led by Andrea Tomasena.
In Berlin we hold our own permit signature, the Bauvorlageberechtigung. We prepare the application ourselves and coordinate the structural, fire safety and energy input with the specialist engineers. You do not need a second office to sign it, and nobody outside the studio changes the design before it reaches the Bauamt.
How long a project in Berlin takes is mostly decided before work starts on site. It depends on whether the application is complete the first time, whether heritage or Milieuschutz rules apply and whether the construction drawings are ready before the firms start.
We look at the building, the structure and the planning rules and establish whether your project needs an application. If the building is listed or in a Milieuschutz area, we check that before design. In unclear cases we apply for a preliminary ruling, the Bauvorbescheid.
Permits in an AltbauFloor plans, sections, elevations and the permit drawings with all specialist input. We file digitally, watch for the confirmed completeness and document the deadline.
The new deadlines in 2026Drawings at 1:50, 1:20 and 1:5, joinery details and specifications that let the firms quote on the same basis. We then run the site under work stage 8 and hand over as-built drawings at the end.
Construction management in BerlinWe follow the HOAI, the German fee framework for architects and engineers. What matters to you is less the stage number than when you decide what. A project including design and construction typically takes six to twelve months.
We come to you or talk by video and hear what you plan, by when and with what budget.
Stages 1 and 2: survey, existing records, options and a first cost framework. Most of our residential projects in Berlin come to €1,500 to €3,000 per square metre.
Stage 3: floor plans, sections, elevations and a first material direction. Changes are still cheap at this point, because only the drawings change.
Stage 4: the Bauantrag with structural, fire safety and energy documents, filed digitally. The authority checks completeness within 14 working days at most.
Stages 5 to 7: detail drawings, specifications, quotes from several firms and a comparison that also shows what each quote leaves out.
Stages 8 and 9: weekly site meetings, acceptance, snag list and as-built drawings. We stay involved through the warranty period.
Then four short questions. We reply within one working day, with no obligation. We speak English, German and Spanish.
Across our two studios, most of our new work comes through recommendations from past clients. 5.0 stars on Google, 5 reviews for our Berlin studio.
"After speaking with them, I knew I didn't need to look elsewhere. Thrilled with the result, highly recommend."
"They gave us excellent advice and ensured smooth implementation with their craftsmen."
"They quickly grasped my taste, found the perfect products, and arranged appointments."
"Tell us about your property, your timeline, what you are hoping for. We will come to you, listen, and present a concept and a realistic cost estimate, before you commit to anything."
We come to you · One project slot remaining for autumn 2026
