©Ossip van Duivenbode, Frank Hanswijk, Orange Architects

In 2019, the former PTT building constructed in 1951 on Binnenrotte underwent a transformation from a structure full of equipment to a structure full of apartments, with a restaurant on the ground floor. The building is located close to the spot where Rotterdam was founded. Since 2007 the building, which had been vacant for a long time, had no entrance from the market side. With the construction of the adjoining building, the entrance court of the PTT building disappeared. With the transformation, the building once again connects with the market square, which has attracted more metropolitan programming in recent years.

The design comprises twenty studio apartments slotted into the generously dimensioned structure. Floor heights of almost 4.5 m give the apartments an exceptionally spacious feel. The apartments also benefit from the wonderful view of the metropolitan cityscape of Rotterdam. The facade facing the market square has been modified to create outdoor spaces and draw more daylight into the building. The lower two floors have French balconies, while a continuous balcony runs along the third floor. The apartments on the tall roof level have loggias. Balconies are finished with metal sheets and fine-meshed balustrades. All additions such as window frames and openable components, metal sheeting and balconies are finished in a dark brown-black colour, allowing the second life of the building to manifest itself as a new architectural layer. All openings on the ground floor have been extended to the ground and fitted with tall steel frames, creating a relationship between the restaurant interior and the market terrace. Thanks to their dark-coated metal profiles, the new entrances on the market side contrast with the brickwork facade.

The roof tiles on the market side have been replaced with solar slates in a neutral, dark colour. As a result, these PV panels are practically invisible, and the high-quality aesthetic appearance of the roof has been preserved. The energy concept has been customized for this building. Residual heat from the data equipment of the KPN servers in the basement is used to preheat the tap water and to heat the floors in the apartments and restaurant. Water is also heated with solar boilers on the flat roof at the rear of the building. The building is heated and cooled with electric heat pumps. Enough energy is generated to supply the needs of almost all apartments and some of the restaurant.

Project Sheets
Site: Rotterdam, The Netherlands
Design: 2017
Realisation: 2019
Size: 3.585 mq
Architect: Orange Architects
Client: private
Advisors: Nick Nieuwenhuizen, Ingenieursbureau IOB, De Mik Adviesbureau, LBP | SIGHT, S&W Consultancy, BOAG
Contractor: BIK Bouw
Solar panels roof: Exasun, Wattco