The urban questions that architectural projects are constrained by are not only formal in nature. The colour of the chosen materials must also guarantee harmony between a new construction and its environment. The choice of colours is constrained by regulations that are sometimes very strict, and yet these regulations depend on tools that are largely open to subjective assessment. It sometimes seems easy to decide which colours should be dominant in a given location, but how can colours be classified in accordance with quantified criteria? Luan Nguyen, a young architectural engineer at the University of Liege has laid the foundations for a standardized and objective method(1) for characterizing the dominant color of a house, street, neighbourhood or city. Apart from compliance with regulations, a tool such as this one opens up a lot of possibilities for better understanding the extent of colour trends in an urban environment.

What is the dominant color of towns? This is the question addressed by Luan Nguyen, who is due to defend his thesis in a few months’ time under the supervision of Jacques Teller, at LEMA (Local Environment Management and Analysis), in the ArGEnCo department of the Faculty of Applied Sciences at ULg. In his search for answers, the young architectural engineer published the results of an efficient, quantified and standardized method which promises a palette of varied applications.

Having studied fine art for a period, in the hope of becoming an illustrator, it was no surprise that Luan Nguyen should take an interest in questions related to colour during the course of his studies as an architectural engineer. His end-of-study thesis had already focussed on this subject by dealing with architectural constructions but had not looked at the problem from a wider urban perspective. He adopted a more global approach to the question based on his professional life outside the University. As the head of a firm of architects which he himself founded, Luan Nguyen became aware that, contrary to the old adage, personal tastes and colours were indeed open to discussion.  

Regulations on subjective criteria

The construction of any dwelling is governed by a series of urban constraints the aim of which is to guarantee architectural harmony between a new construction and the environment. This set of regulations, which can be constraining to a greater or lesser degree, depending on the town or neighbourhood in question, very often imposes a specific colour palette, or a single colour. “The drawback of this is the indecision related to the characterization of this colour. When a new brick needs to be chosen before the construction of a new building, a specific shade of colour is imposed, such as red, brown or light grey. The terms used are quite vague, flowery and subject to personal interpretation. When we appear before the municipal officer, he may well consider that the brick we are showing him is a brownish colour while it may appear red to us”, says Luan Nguyen. This is further complicated by the fact that the colour of a brick will not be the same inside (due to the artificial lighting of the community house), as outside, and will vary even more according to the changing light at different times of the day. Finally, judging the exactness of the colour of an entire wall based on a single brick can only ever be approximate.

In Wallonia, regulatory statutes in relation to colour remain very vague and rudimentary. By taking an objective approach to the problem, the researcher observed that these imprecisions were problematic on a Europe-wide scale. The tool most often used is still a chromatic chart which is arranged according to colour samples from a street, city or country and which is subject to a visual qualitative examination. The use of a colorimeter that yields very precise colour coordinates, can only do so for a very small surface of a facade and does not precisely identify the “average” or dominant colour of a wall.

“In reaction to this observation, I began by asking myself a first question which would help me to apply my research on a city-wide scale. How might one suggest a method for the objective characterization of colour”? It is certainly not about offering a tool to assist municipal regulations. The challenge is a much more fundamental one. In terms of architecture, how can we go from an approach based on qualitative appreciation to a quantitative appreciation of colour?

(1) NGUYN LN., TELLER J.,Color in the urban environment: A user-oriented protocol for chromatic characterization and the development of a parametric typology, Color Research and Application, 2016