Donna’s Rock

VERTICAL is the result of a collaboration between five different architects. The architect Donna van Milligen Bielke imagined a “rock in the landscape”: here she explains the idea behind her design.



Five architects means five styles and five ways of working. Nevertheless, the result of VERTICAL is a unique design consisting of complementary elements. In this series, we talk to the architects about the ideas behind their designs and their way of working. Donna van Milligen Bielke (1983) is one of these five architects. We visited her in her studio on the Keizersgracht in Amsterdam.

“When I began working on the design, the taller tower by NL Architects was already in a fairly advanced state of development. The starting point for the design of the taller tower was a stack of landscapes. These use various types of green, which connect with the surrounding landscape of the Bretten area (the natural landscape around Sloterdijk). The tower will have a very transparent character. To create contrast, the starting point for the design of the lower tower was that it should be a solid, sturdy building.”

The lower tower of VERTICAL
The colours of the façade resemble natural strata

Biodiversity as architectural detail

“I designed a horizontally-heavy, layered building consisting of a compact stack of apartments. Instead of focusing on green, the design highlights biodiversity, including animals and insects. My final design has the appearance of a solid rock. The colours used in the façade resemble the natural strata that are often seen in rocky landscapes. These will be realised using dyed concrete. The design includes various types of habitats for animals, such as nest holes for swifts, other small birds and bats. The façades are fairly plain. By establishing a rhythm in the pattern of openings for the animal nesting areas, biodiversity becomes an architectural detail.”


“Although a clear contrast can be seen between the two towers, they also complement each other very well. They look different, but in terms of biodiversity they form a collective whole. The idea is that ‘my’ nesting birds and bats should eat the insects from NL Architects’ green tower. I see my design as a rock in the Bretten landscape, one that protrudes above the green ‘blanket’ that has been pulled across the building. It is a place for both people and animals, a solid layer cake surrounded by nature.”

First sketch design of the green carpet pulled across the buildings


“I love heavy, assertive architecture. I prefer not to create everyday designs. I also love applying classical logic in new ways. For example, you might expect the bottom layer of a building to have the thickest columns, which subsequently become thinner with each floor. While my design does contain classical proportions, these are applied in a way that appears more random than the classical logic often used in the design of temples in the past. Also, I’m always looking for reasons to build the things that appeal to me personally. I want my buildings to be special. When people cycle past, I don’t want them to think: ‘I’ve seen this before’.”

The model is put together layer by layer

“I don’t pay much attention to architectural references. Personally, I think this is a good thing, because it means the design is really my own creation. At the same time, it often raises the question: ‘how are we going to build it?’. At that moment, I do start to look for examples that relate to my ideas. I try to create something that is unique, rather than simply a collection of elements that already exist.”

Impression of the design. Upper part by Donna van Milligen Bielke, lower part by Chris Collaris.

On Chris

“A nice contrast in the design is that my robust, heavy building rests on the layer designed by the architect Chris Collaris. In his design, Chris chose a natural, grey, wooden façade, which will be somewhat lighter in reality than is shown in the impression above. The fact that a massive, concrete building will be built on top of this makes it quite special. The funny thing is that while I love symmetry, Chris wants everything to be asymmetrical. But this wasn’t a problem. We worked it out pretty well, if I say so myself.”