If you’re working in construction, or studying engineering or architecture you might have heard the phrase “parametric design” being thrown around a lot in the past years. Having recently been introduced to the concept, I felt it would be useful to write something to explain to those who, like me, didn’t know the first thing about parametric design. There’s no formally agreed upon definition, but from reading this article, you’ll understand what people are generally referring to when they talk about parametric solutions and design in the 21st century.
“Parametric” comes from the input parameters, which constrain the design. The basic idea is that an adjustment of one of the design constraints or conditions, leads to an instantaneous change in the building model. This is what industry-leading software can accomplish at the moment, a building plan which instantly refreshes and re-designs when a parameter (such as building height) is adjusted.
A formal definition
To provide an academic definition of parametric design, Andrew Sears (IST) stated in 2007 that parametric design is:
“a process based on algorithmic thinking that enables the expression of parametrics and rules that together, define, enlist and clarify the relationship between design intent and design responses”
There is a lot to unpack there, but ‘Algorithmic thinking’ is a good place to start:
The mention of the word algorithm, or algorithmic for most of us, will bring our minds towards computer science, AI and machine learning. In 2022, this is the domain where parametric technology and design is growing and expanding. However, the origins of the idea long pre-date modern computing.
The Sagrada Familia, Barcelona. Under construction since 1882. Due to be completed in 2026–2028.
The Sagrada Familia, Barcelona.
The commonly told origin story of Parametric Design harks back to the practices of legendary Catalan architect Antoni Gaudí. Among his many accolades and masterpieces, he is credited for inventing the practice.
If you’re like me, you’re wondering: “How on earth could Gaudí. accomplish an “interactive” building design model without modern technology?”
Following the Thread
Effectively, Gaudí availed of gravity, and physics to model his buildings. He made models of his buildings hung upside down, modelled through hanging chains. With this approach, a “tightening” of one of the chains could, in effect, reduce the building height, and pull the other chains with it as appropriate. In Gaudí’s system, the tightening and loosening of a chain was the input parameter, with the output being reflected in the entire model, as below.
Gaudi’s Chain Model. The upside-down model could be “inverted” using a mirror or photograph.
Gaudi's Chain Model. The model could be inverted using a mirror or photograph
Modern Day Gaudi
While the origins of parametric design lie in these beautiful and creative works of a master architect, the modern approach brings more pragmatic benefits. When computers, physics engines and top-class engineers set their sights on parametrically modelling a building in 3D, the benefits are the kind of “resource optimization”, which appeals equally as much to financers, investors, and sustainability engineers as it does to pure architects.
A parametric design in 2022
A typical modern parametric design allows for consideration of more combinations of designs. For a typical large apartment building, apartment units are not drawn by hand and adjusted according to the human eye. They are optimally generated by computers, constantly working to re-adjust the entire building. When one minor detail is changed, the rest of the building plan snaps into place around the change. If you haven’t seen this in action, it’s incredible! Innovators in the area, including OMRT, among others, are usually happy to organize demonstrations of the technology.
The benefits of a parametric design
In addition to the unusual features and aesthetic features that can come about from the parametric process, à la Gaudí, the benefits are highly practical. In 2022, with State-of-the-Art parametric technology, the practical benefits are:
Design time reduced up to 80%
Use of site footprint is optimised by an average 20%, due to computers considering more design permutations than humans can.
Numerous, comparable plans can be easily created, with low extra effort
Minor tweaks to design requirements can be rapidly (instantly after configuration) realized.
At OMRT, as an example, all projects start with an initial “wiring of the system” for each project for a few weeks. After this inital phase is complete, a highly flexible, adaptable parametric blueprint is created for the project.
Why aren’t all buildings designed this way?
Change always takes time! In big industries such as banking and construction, a better idea often takes years to sink in. The construction sector is currently in the midst of a slow and steady march towards these “better ways”, not only in parametric design, but in other technologies in general. It can always be difficult to champion change, but it’s getting easier for key decision makers every year, as parametric design becomes more and more proven in the real-estate world.