Posts Tagged ‘bottom-up design’

From Top Down to Bottom Up

Generative design tools flip the script of architectural thinking

by Brett Duesing, Obleo Design Media

“Some might view computational design is just making some weird or crazy form,” says architectural designer Woo Jae Sung.  The 3D shapes may look arbitrary, but the method behind them is not.  “Contrary to the misconception, generative modeling is based on rationalism.  Our newly developed parametric tools were based on the needs of bottom-up design thinking.”

Designers have two different starting points when conceiving new structural forms, top-down and bottom-up.  Top-down is the classical, Cartesian-center technique of picking the overall shape first and then filling in the parts.  Bottom-up, as the name implies, is the opposite: it starts with geometric components as the initial building blocks.  Through repetition and variation according to logical rules, they grow to define larger systems.

Bottom-up conceptual approaches are found throughout other art disciplines, but it is still rare in architecture.  But Sung sees bottom-up as up and coming.  Sung recently taught a workshop at Cornell, where architectural students experiment with generating highly complex 3D forms by automatically repeating patterns of components.  The workshop uses the newly released application Grasshopper, a parametric plug-in for Rhinoceros’ 3D NURBS modeler.

“In my perspective, the generative design process is not a sub-discipline in architecture, but rather another paradigm,” says Sung.  “Traditional design tools prohibited us from thinking bottom-up, while parametric or generative tools are broadening our design perspective.”

Sung publishes his own Grasshopper Tutorial, a primer of getting started in the program, for Rhino users everywhere.  The tutorials are free on his blog,  Sung says the tutorial content comes out of his own experiments in the software, where he tests his bottom-up theories and learns how to translate them into fully realized computer models.

“Before the advent of parametric and generative tools, doing bottom-up design was a time-consuming, painful, and rigorous process,” says Sung.   “Changes in parameters or relationships between objects meant that entire model should be done manually from the scratch.” He cites works by Eduardo Arroyo or Ciro Najle as examples of bottom-up processes without computer aid.

But with generative digital tools that can easily program geometric patterns, Sung and other a bottom-up artists now have a clearer opportunity to flip the script, so to speak, on the dominant paradigm of top-down thinking.

Housing Block ? Construction of Unite d’habitation in 1945. Le Corbusier’s housing layouts were heavily prescribed by a top?down Cartesian framework.

Housing Block: Construction of Unite d’habitation in 1945. Le Corbusier’s housing layouts were heavily prescribed by a top-down Cartesian framework.

Escaping from the grid

Tradition design tools, construction methods, and habit of mind have reinforced top-down thinking.  Look around at the environments where we live and work, and it is obvious that most of them began life as T-squared outlines on the drawing board.

Sung is starting to see generative output enter into real-world projects, although their application seems to be limited to textural additives, in the form of “crazy” contemporary ornamental patterns on wall panels of a building that was otherwise produced through top-down processes.


Ground rules– Woo Jae Sung’s bottom-up apartment alternative begins with a group of circles nest inside an acute angle. The circles can be rearranged within this boundary in different configurations. A wider angle grows the area of the circles.

Sung demonstrates that bottom-up design can go quite a bit deeper, to the point of defining the entire building form.  Recently, Sung explored the design of the Unite D’habitation, Marseille by Le Corbusier.  Considered iconic in modern architectural history, the 1945 housing block became a template of today’s urban living.

“My research revealed that unit types were not based on typology but heavily influenced by the rigid grid system,” says Sung, who re-organized the basic amenities of the complex by using bottom-up processes, which avoid the regimented repetition of the original Marseilles building while adding greater flexibility to the sizes and layouts of individual units.  “I wanted to propose an alternative way of making architecture based on the internal logic of the relationships, rather than the grid.”

The cylindrical re-conception allows for varied room configurations based on a set of basic geometric rules.  Like cross-sections of a tree, the roughly circular building floor plans resemble one another, but are also each unique.  As the floor layouts vary in form, the vertical supports of the cylinder gently curve back and forth, giving varied character to both the interior and the exterior.  Sung found the optimal solution for ten different floor plans in Grasshopper.

“I think this shows a different application of the parametric tool on architecture other than just wall patterns or mullions,” says Sung.  “Here the parametric tool is playing active role in generating form.

Various angle-circle configurations are assembled as a ring.  Since the <a href=

Natural Transformations

One of the appeals of a layered bottom-up process is that it is closer to that of natural organic growth, and so are the results.  Biological complexity is all bottom-up:  from molecules to cells, cells to tissues, and tissues to organisms.

Berkeley professor Christopher Alexander has literally filled volumes with good examples of form from nature and vernacular architecture, and bad examples from contemporary buildings in his book series, “The Nature of Order.”  He argues that top-down architecture, rooted as it is in abstract images and Cartesian grids, ends up lacking some hard-to-articulate quality.  “Soul” might be a way to put it.  In terms of experience, spaces created by top-down structures of mass-produced components can feel impersonal, cold, or “dead,” while buildings made through more organic generative methods seem to resonate as friendly, warm, and vitalizing.

These benefits may be subjective, but Sung’s attraction to the new design strategy originates more from the latitude it gives the designer when the grid no longer rules form.  “For me, bottom-up design process means control over power, flexibility over rigidity, and possibility over stability.”

Building Differently

A series of transformations within Grasshopper turns each angle into apartment units. A Voronoi algorithm turns the circles into room shapes; each ring design represents a unique high-rise floor plan.


Generative modeling tools like Grasshopper has opened the door to bottom-up design in architectural studios, but the remaining shift in perspective lies in construction site.  Concrete and steel – the cast-mold and frame-surface systems that now dominate construction – keep architects snapped into the grid.

“To build parametric-driven models, you need a mass-customization process, which requires construction paradigm change from cast-mold and frame-surface to sculpturing-modeling,” explains Sung.  “In the fields outside of architecture, we can see this happening.”

In making the quintessential top-down structure of Unite d’habitation, Le Corbusier drew inspiration for its structural system from ocean liners.  In what might be the future trend in 21st century architecture, bottom-up designers might look to the jet.  Aerospace parts exhibit strong, complex forms without the use of cast or frame systems.

“Considering that architecture has fallen behind other fields in adopting new ideas or methods,” says Sung, “sooner or later, the new paradigm will be more actively applied to architecture, and so will the application of generative modeling.”

Bottoms Up - The alternative housing complex model fleshed out in Rhinoceros after form-generation in Grasshopper. The slight variation in floor plans leads to organic curvatures to interior and exterior structural elements and a housing “block” where no two units are the same.

About Woo Jae Sung
Architect Woo Jae Sung is a graduate of Yonsei University, Seoul, Korea, and Cornell University’s School of Architecture in New York.  For more of Woo Jae Sung’s architectural examples and the latest edition of his Grasshopper tutorial, visit:

About Grasshopper
For designers who are exploring new shapes using generative algorithms, Grasshopper™ is a graphical algorithm editor tightly integrated with Rhino’s 3-D modeling tools. Unlike RhinoScript, Grasshopper requires no knowledge of programming or scripting, but still allows designers to build form generators from the simple to the awe-inspiring.  For more information, please visit: