German bombs destroyed the historic center of Rotterdam at the start of World War II, and, ever since, the city has worked to establish a radically new and modern identity. This has led to a sometimes willful emphasis on form-making, but also an openness to experimentation.

Both of these tendencies can be seen in the 38 cube houses designed in the early 1980s by architect Piet Blom in Rotterdam's city center. Angled boxes on columns, the houses stand above and around an elevated street, the Overblaak, which serves as a bridge over the Blaak, a busy road connecting a public market square with the old harbor. Blom intended the elevated street to be a sheltered yet public space for shops, businesses, and play areas. And he designed the angled houses to resemble trees, so he called the complex Blaak Forest.

As an intermediate kind of public space, the Overblaak was not very successful. But the cube houses, in spite of their difficult floor plans and slanting walls, fared better. They are single-family homes with 975 square feet of space on three floors. At each end of the complex, Blom placed a Superkubus or supercube. The one to the north, on the side of the marketplace, was intended to be commercial space but was never fully used, and its top floor was not even completed. The supercube to the south, on the side of the old harbor, was built to house a school for architects.

Enter Personal Architecture (P-A). In 2009, this young Rotterdam-based firm of Sander van Schaik and Maarten Polkamp refurbished the southern supercube as a Stayokay youth hostel. So when Exodus, a foundation that helps ex-convicts on parole, decided to move to the Blaak Forest, it went to the firm that was already familiar with the vagaries of Blom's design.

Concerned about security, neighbors fought the halfway house project in court, but Exodus prevailed. The supercube on the north, owned by the local housing association and rented to Exodus, now provides 20 rooms for ex-cons (and one for a staff member on night duty) and shared living space for both men and women transitioning from prison.

But before Exodus could move in, the supercube required an extreme makeover. “To make this oddly shaped space of 13,000 square feet suitable for its new use, we had to do a major structural intervention,” says van Schaik. The architects removed the column at the center of the cube, replacing it with an open shaft that serves as an atrium for all four floors. That meant transferring the weight of the upper floors to steel portals at the four corners. Within the atrium, P-A added various functions connected by stairs: reception and pantry on the ground floor, washing and storage spaces on the floors with the residents' rooms, a kitchen on the fourth floor, and a lounge above that. Everything P-A added to the supercube is orthogonal, creating a visual distinction from Blom's overbearing diagonals.

The original stairs—located at two corners of the cube—now serve as emergency exits. On the new stairwell, nets cover openings as a safety measure. To improve acoustics, the architects added felt to the outside of the stairwell on the top and bottom floors, and these surfaces have turned out to be handy bulletin boards as well.

The central atrium is the heart of the renewed supercube, says van Schaik. “It creates not only a physical but also a visual connection between the floors, which is important for people who are learning to live with others again.” Moreover, it brings daylight inside and pulls warm air up, solving two problems that had bedeviled the original building. Warm air is now collected and pumped to a heat-exchange installation. P-A also added new windows—three on the fourth floor to provide views outside and six at the tip for ventilation.

The architect designed the project to encourage interaction among the inhabitants, who spend anywhere between nine and 12 months at the facility. The communal kitchen and dining space on the fourth floor draw people upstairs and are complemented on the other side of the atrium by a living room where residents can relax or work on computers, a smoking area, and a glass-fronted consulting room for private conversations. A cozy lounge sits like a crow's nest above the common spaces, just below the tip of the cube. With a grass-green rug and a television for watching sporting events, it has earned the nickname De Kuip, after the local soccer stadium.

Restoring the residents' sense of individuality was an important goal of the architecture. Small elements—such as painted-wood doorposts, a light in front of each room, large photographs of well-known spots in Rotterdam, and a private shower and toilet in each unit—provide dignity to the living experience. Beds and closets had to be custom-built to be durable and to fit in the unorthodox spaces. Some of the rooms reveal the exigencies of living in an upended cube: a bed in one room cantilevers out from the wall, and its occupant has cut out pieces of paper to cover windows that look directly into the neighboring cube.

Residents in the Exodus program can leave the building during the day but are not allowed to drink alcohol—even off-site—and must take a breath test when they return. The location in the city center helps reinsert them in society, while also providing a supportive retreat. For a facility serving former prisoners in a building with a checkered history, the place has a convivial atmosphere, especially on the communal fourth floor. And bedrooms, small though they are, feel like dwellings rather than cells. Exodus is a halfway house, with the emphasis on “house.” One former convict living there recently even placed a mat in front of his door spelling out in florid letters: home.


Architectural client:
Woonbron, Marten Treffers, Kruisplein 25L, Rotterdam, +3110 275 5300,
End user, interior client:
Stichting Exodus Rotterdam, Lara van der Well, Westzeedijk 116, Rotterdam, +3110 436 9590,

Woonbron, Marten Treffers, Kruisplein 25l, Rotterdam, +3110 275 5300,

Personal Architecture BNA
Graaf Florisstraat 62a, Rotterdam
+3110 886 5093

Personnel in architect's firm who should receive special credit:
Partner in charge: Maarten Polkamp (registered architect)
Partner in charge:  Sander van Schaik (registered architect)    
Assistent architect: Froukje van de Klundert (registered architect)
Assistent architect: Leendert van Grinsven
Assistent architect: Wiepkjen Kingma (registered architect)

Interior designer:
Personal Architecture BNA

Structural engineers: IMd raadgevende ingenieurs, Piekstraat 77, Rotterdam, +3110 201 2360,
Building fysics: DGMR, Casuariestraat 5, Den Haag, +3170 350 3999,
Building management: Woonbron Ontwikkelbedrijf, Eric Coopmans, Van Nelleweg 3042, Rotterdam, +3110 751 6600,

- Consultant Installation work: De Blaay-van den Bogaard Raadgevende Ingenieurs B.V., Westblaak 35, Rotterdam, +3110 275 7171,

General contractor:
Hijbeko B.V., Rhijnspoor 235, Capelle aan den Ijssel

Electrical system:
Rijnsburger Elektrotechniek B.V., Wil Koek, Ondernemingsweg 52, Alphen aan den Rijn, +3117 243 0911
Brabant Installatie Techniek B.V., Vaartveld 15, Roosendaal, +3116 553 0499,
Altena Installatie B.V., Beatrixhaven 4, Warmerdam, +31183505688,
Ferro Design, Erik Born, Overschiese Dorpsstraat 52, Rotterdam, +3110 415 3384,

René de Wit, Blauwoogvlinder 37, Breda, +31654723600,

Ossip van Duivenbode


13,000 square feet



Completion date:

July 2013



Structural system
Original building: concrete
Construction to create void: steel frame

Skylights: Velux

Wood doors: HPL covered with Formica Colorsystem, by Svedex
Sliding doors: Motion by Svedex
Fire-control doors, security grilles: Firescreen RS120, by Hoefnagels Branddeuren BV

Locksets: by Artitec
Closers: by DORMA Nederland B.V.

Interior finishes
Acoustical ceilings:  By contractor
Cabinetwork and custom woodwork:
- custom woodwork by contractor,
- kitchen by Koolschijn & Zn, Rotterdamseweg 352, Delft, +3115 251 7171,
Paints and stains: Sigma and Glitsa
Wall coverings: Knauf Diamond Board, finished with glass tissue wallpaper/ MDF with HPL
- MDF by contractor
- birch Multiplex by contractor
Plastic laminate: HPL, by Abet BV
Special surfacing: Felt by Eurofelt
Floor and wall tile (cite where used): Mosa colors, 150x150, by Koninklijke Mosa bv
Resilient flooring: Marmoleum by Forbo
Raised flooring:  Finnish spruce plywood,  ( fourth level)
Special interior finishes unique to this project: X-tor steel netting, by Huck

Office furniture: Nelison, Huygenslaan22, Berkel en Rodenrijs, +31622510020,  
Reception furniture: by contractor
Chairs: re-used and second hand
- Nelison
- second hand
Upholstery: Curtains by Woning & Projectstoffering Sparreboom, Jan van Galenstraat 92, Schiedam, +3110 426 6533,

Other furniture:
- beds by Nelison
- cupboards in rooms by Ikea, assembled by Nelison
- photographs covering furniture assembled by Nelison

Interior ambient lighting: By subcontractor
Downlights: By subcontractor
Task lighting: By subcontractor
Dimming System or other lighting controls: By subcontractor

Washbasins: Sphinx by subcontractors
Faucets: Eurostyle, Grohe by subcontractors
Toilets: Sphinx by subcontractors
Water reservoir: Geberit by subcontractors

Other unique products that contribute to sustainability:
The skylights can be opened so natural draft cools the lower floors. This made additional cooling systems unnecessary.