5 5 For more information on “20th Century Architecture”, see: http://www.culture.gouv.fr/Thematiques/Architecture/Architecture-et-cadre-de-vie/Architecture-du-XXe-siecle [Accessed October 7, 2018].
1
Between Architecture and Climate: A Bioclimatic Approach
1.1. Introduction
When André De Herde takes his place at the microphone, we feel that the air thickens with respect and expectation. “André is one of the pioneers of what is called bioclimatism,” Robert Célaire introduces him, also describing him as “professor emeritus, engineer architect, doctor and author of several books on bioclimatic architecture”. These words bring me back to the time when I arrived at an agency as a young graduate engineer-architect from Leuven (not to be confused with Louvain-La-Neuve, which is also in Belgium), and my boss presented me with the Bioclimatic Architecture Guide: Volume 2 as required reading. Without knowing it, André De Herde had a great influence on my architectural approach and production.
He speaks up. His calm voice reveals a great experience in the field. He says he feels honored to be here, in front of the Minister’s Representative and the students, and we, in turn, feel honored to be with him.
He unveils the structure of the conference in three parts: the concepts of bioclimatism, sustainable development and smartness; the “Architecture and Climate” research team created in 1980; and the teaching of architectural engineers at the University of Louvain-La-Neuve. He specifies that there will be around 35 numbered slides, for those who may find the conference long. The framework is set, and the conference can start.
1.2. Bioclimatism
Following the energy crisis, in 1973–1976, architecture schools proposed adding 10 cm of insulation to walls and solar panels on roofs. At no time has the energetic aspect been taken into consideration in the architectural act or the building design.
We offer an alternative to this, one possible answer among other possible answers, without claiming it to be the answer or the ultimate truth.
Our starting point is the observation that every building that we build or renovate is located somewhere, set within a certain climate. All these climates present positive and negative aspects. It is only humid tropical lowland climates that have exclusively negative aspects. The positive aspects are sometimes only at night, or simply because we are at a certain altitude and this enables us to act to guarantee the comfort of the occupants.
For us, from the design phase to the realization phase, the architectural act has two goals. The first is the search for the best match between the habitat – the building, the climate in which the building is located – and the occupant. The occupant is particularly important, because it is them who bring forward the comfort requirements. The four comfort requirements related to energy consumption are winter comfort, summer comfort, breathing comfort and visual comfort. In Belgium’s housing facilities, there is no difficulty in the summer to avoid the use of air conditioning, because buildings can be properly ventilated and offer adequate visual comfort during the day. However, in some cases, there is no way to meet these comfort requirements, and therefore we have to use additional elements, often mechanical ones. This leads us to the second goal: the search for the best possible match between the habitat, the additional facilities and the occupant.
We suggest that architects work in this manner: to design the building that meets the occupant’s goals as much as possible. If this is not enough, then we resort to technology, but not the other way around, as is often the case. When we have completed the entire design process, we will find what type of energy fits it best.
To be able to meet both goals, there are certain notions that the architect must understand, not simply know, but understand in order to be able to play with them. These notions are related to the climate and its characteristics, the comfort requirements of an individual, and the building’s physical features. We pondered how to present these physical notions to architects, so that they could easily understand them and naturally integrate them into their architecture. Thus, strategies were developed, meeting the goals of the above-mentioned four types of comfort: the heating strategy (when the building needs to be heated), the cooling strategy (when it needs to be cooled), the natural lighting strategy, and the ventilation strategy. Each of these strategies is based on a number of physical concepts.
Therefore, bioclimatism means taking the climate into account from the very first design plans: considering the positive aspects of a climate on the one hand, and protecting oneself from the negative aspects, on the other.
So, bioclimatic architecture is not like the trend that is present today: stuffing buildings with more and more systems.
After 20 years, these concepts have begun to be integrated into some buildings. In this context, I ask you a series of questions:
Are we not, in a certain way, stopping architecture? We tell ourselves that we cannot stop architecture. Everything that is said here is at the service of architecture, in no way diminishing the architect’s creativity, or the architectural quality of the architect’s work. I would even say the opposite: taking these notions into account and this approach will increase the architectural quality of the project and the architect’s creativity.
Is there not a risk of habitat mechanization nowadays? What are the responsibilities and the rights given to the occupant nowadays? Can the occupant still open the window? This may sound trivial, but in some recently-built buildings, they say, “above all, do not open the window”.
Is there not a risk of forgetting about other consumption? We focus on winter energy consumption, but there are plenty of other types of energy involved in the building. Is there not a risk of consuming more gray energy than use energy?
1.3. Sustainable development
The end of the 1990s heralded the arrival of what is generally known as the “environmental crisis”, and the “climate crisis” in particular. For those who are still skeptical, here are a few figures: in 1970, there was a concentration of 330 ppm of CO2 in the air. At 350 ppm, climatic stability has been exceeded, and it is not certain whether we can go back. Today the level is around 410 ppm CO2, which is huge. If nothing changes, in 2100, carbon dioxide concentrations will be between 730 and 1020 ppm, depending on the scenario adopted. The last time the 400 ppm level was exceeded was 3 to 5 million years ago: the temperature was 3–4°C higher and the sea level was 5 to 20 m higher than at present.
Architects and the world of construction are responsible for 50% of exploited natural energies, 45% of total energy consumption, 40% of generated waste and 30% of greenhouse gas emissions. We are therefore directly concerned and cannot remain indifferent to these questions.
In this environmental crisis, the buzzword “sustainable development” appeared. People used to say “I am building a passive house, so I am doing something sustainable”, or “I am using ecological materials, so I am doing something sustainable”. In fact, these are all varied aspects of sustainable development, but if this same passive house is 5 km from public transport and you park your 4x4 in front of your garage every day, the whole setting is not really sustainable.
Gro Harlem Brundtland, the first