De Sluiswachter

remarkable and sustainable residential tower

De Sluiswachter is designed by GROUP A in collaboration with a multidisciplinary team and commissioned by SDK Vastgoed. A residential tower with a public plinth and 62 apartments in the Coolhaven in Rotterdam. De Sluiswachter is remarkable, contemporary and progressive, and yet feels comfortably embedded in the ensemble of the 3 existing monuments. A recognisable beacon that, together with Little C, connects east and west.

On an urban level, De Sluiswachter fits in with the existing ensemble of monuments; Puntegale, the Machinist and the Parksluizen pumping station. In contrast to the massive foundations of these monuments, De Sluiswachter is light-footed. The transparent plinth preserves the spatial atmosphere, while creating a secure and pleasant urban structure on a human scale. Important sight lines are preserved because the building mass above 16 metres is reduced by 30%. This strengthens the relationship with the surroundings.

Public space is part of the project. The layout of the landscape is inspired by the urban dynamics of Coolhaven. The ships, bridges, pedestrians and sportsmen, the cafés, restaurants and neighbourhood events. De Sluiswachter embraces these existing activities and provides space for new ones. The Coolhaven stairs, the Coolhavenplein, the quayside and the cafés and co-working space in the plinth of De Sluiswachter create a pleasant outdoor space where people can meet and stay. A nature-inclusive, urban destination along the water; the last stop on the Coolhaven tour.

The sculptural character of De Sluiswachter is strengthened by its unusual use of materials. The outer layer consists of a filigree metal ‘mesh’ that wraps around the building like a transparent ‘dress’. Where there are windows and balconies, residents can slide this layer open to have an open view on the surroundings. Behind this transparent layer is the wooden façade with its alternating open and closed sections. The warm colour of the wood, the shiny closed and glass panels allow De Sluiswachter to blend in with the light and its surroundings.

The layout of the 62 apartments is highly flexible. In the large open living area, the ‘wet cell’ is the only thing that has a fixed position. By means of flexible walls, residents can (re)arrange the space around as they wish, accommodating the stage of life at that moment. The clustering of ‘wet’ facilities, the separation of support and installation, the application of a column structure and the realization of high ceilings (3.1m) make the dwellings freely adaptable and flexible.

De Sluiswachter has its own ecosystem, which uses energy sparingly, welcomes urban nature, closes waste cycles and collects rainwater for cooling and reuse. Just as we reuse donor steel for the skeleton and trees for the wooden floors and walls. De Sluiswachter is part of a high-quality living environment. A place where sustainability is the visible starting point. With plenty of room for greenery, daylight and biodiversity.



SDK Vastgoed


Tender, finalist


Coolhaven, Rotterdam, NL


6,075 sqm


Residential and public spaces in the plinth




Paolo Faleschini


CG maquette

In collaboration with

LOLA (landschapsarchitect, Fabrications (duurzaamheidsarchitect), Rebel (concept & doelgroepen), Kwirkey (mobiliteitsconcept), Softcity (concept en exploitatie plint), Bureau Stadsnatuur (ecologie & natuur)

The makers of this project

Adam Visser

Adam Visser Architect | Partner

Pia Fischer

Pia Fischer Architect | Projectleader

Laura Onnis

Laura Onnis Architect and visual artist

Denny Chan

Denny Chan Architect

Frank Deltrap

Frank Deltrap Architect | Projectleader

Matteo Bettoni

Matteo Bettoni Architect | Projectleader

Charlotte Nieveen van Dijkum

Charlotte Nieveen van Dijkum Architect