Kerto. What else? B​y Charlene Heuer

Kerto - What else?

​B​y Charlene Heuer (Strüby AG​)


The project is situated in Germany in the heart of Berlin. Berlin Mitte. The chosen building is an existing shopping center called Galeria Kaufhof which is facing directly Berlin Alexanderplatz. The project consists of 2 main volumes which are east/west orientated. The volumes are spreading out over 4 stories with different heights. Therefore is a better urban adaptation possible. The duplex apartments are facing 2 sides and can profiting of the attractive city out-looks.


-Asymmetrical volume activates the surrounding building landscape.-Higher Building part West leaves space to "breathe" for the eastern hotel   Park Inn. Not loadbearing facade supports the architectural design to the site.-Asymmetrical facade opens the strictness of the Alexanderplatz.

Main idea is to create a “in Between level”. The connection HUB
Here are not only  taking place common activities  its also a technical level. It works as commons space as well as a hub for statically loads, people movements, lift circulation old/new, cellar space, laundry, bicycle parking, escape staircases, heating facilities  and last but not least an outdoor gym over the roofs of Berlin. Coming together, sport activities an after work drink, communication space and a Bar. The opening hours will be depending on the needs of the prospect inhabitants. 


The project is divided into two houses. House east and house West. It creates 70 new apartments over 4 stories. The offer ranges out from a single or small budget over a short-time partly rentable bonus room until until a  huge cluster apartment for shared living.  Additionally  there is a nursery school, a free planning space and a common level with outdoor gym, cellar boxes, playground and so on. The corridor spaces is reduced to the minimum and its possible to serve with 2 lifts 35 flats. This becomes mainly possible trough the duplex flat system.


The projects offers 200 new bicycle parking spaces. In the inner city Alexanderplatz there are brilliant public transport possibilities. (Train/tram/bus/S-Bahn/Underground).Therefore a car which is owned by the prospect inhabitants must be placed outside of the city center via park and ride. 


-Integration of the irregular existing grid
-Bisection for the timber grid
-Independent lift position of the existing +extension part
-"In-Between" Level as ideal connection hub between old/new

The primary Kerto girder spans north south the secondary east west to be able to create a beautiful visible balcony structure.  The used products are: 
  • Primary slab construction=Main floor girder Kerto-S 51x400mm.
  • Secondary slab construction=Kerto-S Floor Joist 51x400mm 
  • Balcony construction=Kerto-S Floor Joist 51x400mm
  • Roof= Roof rafter Kerto-S 51x400mm.

The Glass dome of the shopping Mall is integrated in the project. The main grid of the existing is used to be the main statically loadbearing system for the vertical loads. All cellar + bathroom boxes are modular and prefabricated and correspond to the German maximum transport possibilities without special permission with a with of 2.55m. No facade cladding necessary. The balcony layer protects the  rough plywood facade for all weather conditions.

City Above the City architecture competition

Plan B : City Above the City architecture competition 

Metsä Wood challenged architects and students around the world to push the boundaries of modern wood building design in the urban environment. Entrants from 40 countries created their Plan B to urbanisation using wood (Kerto® LVL – laminated veneer lumber) as the main material. The task was to design a wooden extension to an existing urban building. The entries were designed to 69 cities worldwide.

Explore the designs