Frans van der Werf

Frans van der Werf is an architect and urban planner, who graduated in the 70s on his award winning project ‘Housing in a Linear City’, in which he advocated Open Building ideas. In 1977, Van der Werf firstly implemented Open Building principles with the project of ‘Molenvliet’. Van der Werf’s book ‘Open Ontwerpen’ (Open Designing in English) is based on 15 years of Open Building practice on an urban and architectural level.

Frans van der Werf emphasizes that Open Building is a strategy for the built environment. He explains that Habraken refrained from actual designing during his career. Designs would place him in a stylistic corner and therefore make his theories less generally accepted. Van der Werf adds to this: “Habraken wanted to be the theorist and supply the method. He didn’t want to be identified with a certain application of Open Building. He wanted to keep the principles clear and open in order to make it generally applicable in all ways.”

Using the term ‘an Open Building’ to depict a specific building or ‘Open Buildings’ in plural form is debatable. Open Building comes from the Dutch term ‘Open Bouwen’ and consists of ‘open’ which has an equal meaning in English and ‘bouwen’ which should be translated to the verb ‘building’. It should not be translated as a noun (which would translated as ‘bebouwing’ instead).

In Habrakens 1961 book ‘De Dragers en de Mensen’, later translated and published in English as ‘Supports: An Alternative to Mass Housing’, N. John Habraken explained Open Building metaphorically: “Open Building makes a distinction between support and infill. The support represents the most permanent parts of the building, like the structure, and can be seen as a bookcase. The infill represents the adaptable part of the building, or in other words the books.”

Van der Werf used the metaphor of the bookcase as coined by Habraken and visualized it with an image of the modular bookcase by Lundia (see below). He used this to explain the clients what the process would look like and what the possibilities and workarounds of Open Building are. Van der Werf adds: “This example makes it down to earth and very easy to understand”. He explains the similarities to Open Building as: “The architect designs the shelves unit, these are more or less permanent. Hereafter the infill is mounted and is more easy to adapt. The parts of the shelves unit are modularly coordinated. They all fit perfectly. This shows that the infill should always fit in the support. The man and the woman in the picture represent the inhabitants.”

Levels of Open Building

As Van der Werf mentions in his book ‘Open Ontwerpen’, Open Building is a strategy based on empowering inhabitants to design and lay-out their own dwelling, which is located in the supports. On a larger scale, the strategy offers different builders the freedom to develop their own architecture within coherent urban fabrics. This is why Open Building distinguishes three levels of intervention, each on a different scale:

1. 'Urban tissue': the design level of interwoven public spaces - for instance streets, courtyards and squares - shaped by built volumes. An urban tissue has a spatial pattern that structures the morphology of a city district causing it recognizable as a whole.

2. 'Support': the architectural level of a collective solid ‘base building’ with space to parcel and - if needed - access spaces like stairwells and corridors. A support allows the allocation of different sized dwellings and a free or flexible lay-out for each of them. Different functions might be added, like shops, ateliers, restaurants and offices.

3. 'Infill': the interior design level of a particular lay-out of a private dwelling by the free assemblage of components like partitions, doors, windows, piping and wiring.

The three design levels of Open Building operate independently but are deeply related. The distinction offers each resident the freedom to get a particular layout of his private home, within a collective support building. It offers a developer the freedom to build architecture within an urban tissue of public outdoor spaces. Thus, it offers citizens on different scales a rich spatial diversity within a larger, coherent environment.

The illustration ‘Levels Open Building’ (see below) shows four levels. Van der Werf explains that the three levels, as described previously, are part of a greater whole. The fourth level, ‘City Structure’, exceeds Open Building in its current definition. Van der Werf emphasizes that this might change in the future. On the other side of the scheme, below the ‘infill’, there could be the level of ‘furniture’. The illustration therefore shows a limited scope of greater whole.

In response to the theory of levels in Open Building, presented below and in Van der Werf’s book ‘Open Ontwerpen’ (Open Designing in English), Habraken wrote that architecture has borders. De built environment shows aspects which surpass the architectural design. It has a zone where architecture stops and urbanism starts. In this area a larger collective determines the boundaries in which architecture moves.

Urbanism, as a task, is not an enlargement of the tasks of architecture, but a different domain on another level with its own actors and own laws. Likewise, architecture stops on a smaller scale because habitation begins, whereby the user determines the interior of his own environment. Shortly: the architectural authority doesn’t extend from chairs to cities but has its own playing field in a broader spectrum.

A support is the commonality of a couple of dwellings. This definition supposes that there are differentiations as well, namely: the infill. The term supports is only applicable when there will be an infill and a clear separation between these two. The support is decided upon by a community and an organisation, such as a construction association (bouwvereniging in Dutch) or a real estate developer. The support offers common areas and structures in which is invested for many generations to come, independent of their individual lifestyle and demands.

Frans van der Werf coins the questions “Why the supports?” and so “Why the infill?”, and answers them himself. From the perspective of the users the answer is easy, it endorses the customization of dwellings and individual lifestyles. The goal is to design supports that literally support the infill and a free layout. For investors and housing associations the long term financial benefits are found in the freedom to divide and redivide the lots in different sizes of dwellings and extend the profitable lifespan of the building.

The supports should be designed for the largest amount of dwellings possible throughout the total lifespan and to facilitate the possibility to merge and split dwellings. The number of front doors and house numbers as well as the deed of division should be adapted and maximised accordingly.

“What is the scope of the supports?” and “Where is border between supports and infill?” are questions of control or authority, explains Frans van der Werf, and touch the principles of Open Building. Van der Werf acknowledges that this border is not set in stone, but rather flexible and different for every project. The supports include the elements which are of common interest, such as circulation spaces, load bearing walls, load bearing floors, and the shafts. In some projects the stairwell, fuse boxes, central heater and the front and back doors are also included.

Supports represent more than a structural skeleton. A support has its own identity and base facilities, which form the spatial expression. All architectural means can be used to create a support for it to become a well-articulated architectural space.

The infill can be defined as a composition of individually customized elements. It is the theoretical and practical answer to the rejected uniformity of mass housing and modernism, where ‘a good house’ is defined by a centralised government. For Open Building on the level of the infill, the inhabitant has the power to decide. This could be described as the essence of Open Building.

An infill can be supplied by the contractor and the architect of the support. But having given them the freedom to create their own space, it’s rather desirable if inhabitants choose a company to design their infill.

In 1993, Van der Werf described an ideal Open Building scenario, which is currently still speculated large on by many architects. In this scenario the individual infill is not a tender, but rather shopping: the inhabitants visit multiple infill shops or infill factories, where the different options are displayed, just like buying a kitchen. In this scenario the architects should rather describe the infill as specifications than a specific product. For the inner walls for example, the strength, thermal insulation, sound insulation and demountability should be described, rather than the type of wall. This way the inhabitants and the suppliers are free to choose, within the scope of the technical requirements.

The factor preventing participation in housing from a breakthrough is the fear of losing control at the side of the real estate developers, as they would often mention: “You don’t know what happens or what will be the result”. The solution lies in the adaptability which is inherent in the infill. If the design from a previous inhabitant does not fit the new inhabitant, the infill can be adapted rather easily.

‘Molenvliet’, is a residential project in Rotterdam Papendrecht, designed by Frans van der Werf and completed in 1977. It is designed with the ideology of the ‘SAR’ (‘Stichting Architecten Research’ or ‘Foundation of Architectural Research’ in English) of which Habraken was the chairman for multiple years. Molenvliet consists of 123 dwellings, of 67 different types of empty customizable units.

Molenvliet features upper dwellings, reachable by a gallery, and ground-floor dwellings. The support consists of floors, load bearing walls, the roof, roof terrasses, galleries and shafts. The infill package, which includes the interior lay out and the façade, is compiled in collaboration with the clients (future inhabitants).

Once the contractor started construction, Van der Werf offered two private infill consultations of one hour with each of the users. During the first meeting they discussed the needed spaces and functions related to the age, hobbies and preferences of each family member. The second meeting, two weeks later, was spent on the confirmation or small changes.

The floor plan as shown is made in cooperation with the family De Waard, during the first consult. The black lines represent the support. These are designed up forehand. The lines in green are the infill, designed in cooperation with the client. Red is used for notes, such as the location of the heating radiator. It is an easy way to show the difference between the support and the infill. At the end of the consult the client got a copy of the floor plan for the technical draughtsman, who converted the plan to a well-structured and technically feasible drawing.

Open Ontwerpen - Frans van der Werf