About us

D:4 was founded in 1997 from a collaboration between business partners Marcus Nitschke and Jörn Focken.

Today we are an interdisciplinary office with offices in Berlin and Hamburg as well as representatives in Tirana and Krems. Our total of 27 employees are trained in the fields of architecture and historic preservation, as well as real estate management, art and cultural history, and social sciences. We attach great importance to an international team as well as a fair gender distribution and it is very important to us to promote our employees and their respective strengths individually.

In addition to the architectural services according to HOAI, we also work on expert opinions and feasibility studies, advise on subsidies and offer project management. In our work in the field of historic preservation, we can draw on more than 20 years of project experience.

We take great pleasure in complex tasks that require unconventional solutions and sensitive approaches and are constantly interested in new ideas and models for sustainable building, living and working!


We are looking for immediately:

  • an architect for design and implementation planning (LP 3-5)

  • one:n architect:in for construction supervision D:4

  • a:n accountant:in on a minijob basis for publishing house & gallery treppe b

> more info


Our service profile in the field of architecture includes all service phases according to HOAI (LPH 1-9). Here we can draw on expertise in new construction, building in existing structures as well as in renovation and maintenance.

In addition, we are active in the field of building evaluation and have many years of practical experience in the analysis of room programs and the creation of usage profiles for individual buildings and larger real estate portfolios.

Furthermore, we prepare energy reports and provide comprehensive energy consulting.


Our employees bring in profound knowledge in dealing with listed buildings. In recent years, monument preservation tasks have become a special focus of our expertise.

Within the scope of these tasks we create:

  • building-historical investigations and building surveys incl. archive research, building research on the building and photo documentation
  • Plans for the preservation of historical monuments
  • Damage documentation and restoration reports
  • Colour diagnostic tests

We also assist our clients in making arrangements with the authorities and other parties involved.


At the interface between architecture and monument preservation, we can advise our clients with our specialist knowledge and many years of experience in the field of sacred buildings. In addition to new construction tasks, our field of activity also includes the accompaniment and support of congregations of all denominations in the management of their properties.

Construction projects in the field of sacred buildings always place special demands on our work: The sensitive analysis of the needs of the congregations, the historical and political contexts of the religious communities and the future visions of our clients for their property define our work. In recent years, we have been able to accompany many congregations in the renovation, redesign, conversion and optimisation of their buildings.


In many of our architectural projects, we work with artists from the design phase onwards. We explicitly understand art as an integral part of architecture, not as an application, as is often the case with "art on building" projects.

In the area of sacred architecture, we support church clients in the implementation of competitions for the artistic design of church interiors and accompany the implementation of the selected works in a moderating capacity.

In addition, D:4 founded the architecture gallery and the associated publishing house treppe b in 2016. The gallery space in the Corbusierhaus Berlin hosts temporary exhibitions on post-war modernist architecture as well as contemporary positions, but is also used for concerts and other events.


Today, many construction projects in the social and cultural sector can be co-financed by subsidies. We support our clients in the acquisition, application and administration of project-related funding, whether state, federal or EU funding.


The preparation of studies and expert opinions for individual buildings or larger building stocks is an important part of our work. Here we work with both private and public clients and create concept studies, feasibility studies, monument preservation analyses, but also energetic reports and profitability analyses.

We accompany our clients in operational decisions for the realization of their projects in an individual and trustful cooperation. Due to our interdisciplinary team we are not only able to deal with architectural and monument preservation issues, but always include political, social and historical contexts in our evaluations and recommendations.

Our individual achievements are:

  • Feasibility studies
  • Utilization concepts
  • Climate protection concepts/energy concepts
  • Valuation of real estate
  • Financing concepts
  • Real Estate Consulting


Refurbishment Wilmersdorf Mosque
In what is now the 6th construction phase of the renovation of the Wilmersdorf mosque, the floor is currently being newly installed. A neutral screed is to complete the interior.
This will be followed by minor work to complete the interior refurbishment. We look forward to presenting the final result to you soon.

New interior design of the Paul-Gerhardt church interior

We are planning a careful redesign of the interior of the church for the Paul Gerhardt Lutheran congregation in Lichtenberg. This should meet today's congregational and liturgical requirements. The design should further develop the history of the place and result in an appealing overall architectural concept.

As with many of our projects, we work in intensive dialogue and with the support of the church community to achieve a sustainable result.


> Community Magazine Paul-Gerhardt_S.24-27

> About the parish