Energy renovation is not an end in itself. What we want is comfort, more durable, more beautiful buildings, etc., at the lowest cost. The technical responses are therefore only solutions, means, which must therefore be adapted to the objectives. However, these cannot be interchangeable from one operation to another, from one user to another, from one inhabitant to another, quite simply because everyone's habits are different.
The energy renovation must then be accompanied by a real architectural programming approach allowing a fair objectification, and therefore a good match between the technical solutions and the reality of the people who will live or already live in the premises concerned.
Defining the need for energy renovation
Have we asked ourselves this question: What are we looking for? An energy gain? An improvement of a criterion in a calculation note? An energy consumption threshold? The goal is comfort, technique is not an objective. One of the fundamental points, and the one that we will develop, is knowing “Who needs to renovate? ". Indeed, if we renovate only for a heritage calculation, working only on the figure then, it's simple, it's accounting, depreciable, linear... It's important, but it's not the essential, because if the figures are used to quantify, they forget the essential: the human. If we have to renovate, it is not for such an important climate issue either, but for the fundamental right of our fellow citizens, that of a decent habitat.
The right to adequate housing has been recognized as an integral part of the right to an adequate standard of living in the Universal Declaration of Human Rights of 1948 and the International Covenant on Economic, Social and Cultural Rights of 1966. The recurrent jurisprudence of the European Court of Human Rights reinforces the rule.
This explains in particular why the notion of “fuel poverty” was developed. This relates the service (heating, insulation, thermal comfort, sanitary quality of spaces) to the cost of this service. If this report is unfavorable to the occupant, we speak of precariousness. Renovation is therefore an issue of Dignity towards our fellow citizens.
Theoretical economics are sometimes only theoretical
Our example lives alone in a small 70m² house that she has lived in for decades. His house dates from the 1960s, single-glazed joinery without insulation and built in concrete blocks. The main room is heated via a wood stove, the 2 bedrooms and the bathroom are not. It consumes 4 cubic meters per year for its heating. An electric cumulus produces hot water for the small household.
One day, she receives a disturbing call asking her how are the windows of her house, her insulation. A counselor moves to make an energy balance. The note falls: Class F. As it is not taxable, numerous financial aids will allow it to finance the operation with a very low remaining charge of €50/month over 10 years. On the program: External insulation, change ofjoinery for PVC, double flow ventilation, air/water heat pump with installation of radiators.
The interlocutor was serious, after 6 months everything is finalized, but she no longer recognizes her house. She no longer hears the street, she no longer has her wood-burning stove, she no longer understands all the heating buttons, etc. She has the impression that the house is darker, tunnel effect of ITE associated with very wide uprights of PVC...
But did we ask her what she wanted? What she felt? And what about the long-term carbon cost of this work, the initial consumption being almost nil?
A technical installation without pedagogy, involvement or training of users will not bring the expected effects and could even lead to a rebound effect, because the technique is very greedy in rare raw materials... not to mention our trade deficit, these products being essentially manufactured somewhere else !
Energy renovation beyond architectural, environmental and technical programming
If we consider the human criterion as essential, the answer can no longer be only technical (insulation, ventilation, heating, etc.). Dignity requires the involvement of the occupants, their right to participate in this renovation, whether through their participation in the definition of objectives, through their training and their good understanding of the issues and good methods.
In two words: the renovation program cannot only be technical, it must also be functional by integrating in particular the question of proper use, and therefore the human question. Because, beyond energy and/or carbon cost savings, short, medium and long-term needs must also be considered.
The example taken above is symptomatic of a renovation taking into account only the technical point of view. And even if this is useful, what is the point of installing double flow ventilation if sleeping with the window open, summer and winter, divides the efficiency by 5? We are of course not saying that the solution is useless, but if it is misunderstood, and therefore misused, or if it is not deactivatable when needed, it can become so. And the same goes for tertiary buildings when doors are jammed with chairs to create drafts, to overcome access control during the cigarette break, or any other trick of the occupants / users resuming their rights.
So what to do?
Two points seem essential:
A renovation cannot be ONLY energetic , in the same way that it cannot be ONLY architectural without thinking about the comfort of the inhabitants and users. Consequently, the question of consultation, whether or not it is seen as predominant in the architectural programming process  , must indeed be studied for any operation. For several reasons :
- Not everyone lives the same way and does not have the same needs. To be convinced of this, it is enough to see the inhabitants or users of the same building opening the window or, conversely, complaining about the cold, according to habits and sensitivities.
- Any equipment not included and not integrated will be misused, or not used at all, and therefore will therefore risk beingmisaligned (double-flow ventilation, radiant ceilings, etc.).
For personalization of accommodation.
Housing must be, even more than before, adaptable to individual uses. That is to say that any occupant must be able to use it in the way he wishes, without harming his neighbors or the energy consumption of the entire building. Each dwelling must be freely configurable, each inhabitant must therefore have been trained in the uses and manipulation, necessarily simple and intuitive, of the management bodies. We therefore call for a real personalization of housing, far from the mass production or very formatted which has long been the rule.
Is it possible ?
This is of course far from obvious! And it is even less so if we continue on the path of the current technological escalation that has invaded buildings and the city. Or rather, this is possible if these meters, regulators, thermostats and various screens are installed in accordance with the needs. If they contribute to the comfort of the inhabitants and are VERY easily appropriated, customizable, they will be understood and used.
We therefore believe that an energy renovation operation must be based on two coherent principles:
- If the cheapest square meter to build, run and maintain is the one we don't build  , an architectural programming approach will make it possible to optimize the spaces as well as possible (and therefore limit them), and above all to use the contributions of sociology and feedback from various experiences facilitating the appropriation of equipment by the inhabitants;
- This approach will also make it possible to limit equipment to those that will be useful for uses, in full agreement with the frugality issues of construction and often the issues of a low tech approach, refusing useless installations which could be replaced by inactive systems. (for example, good thermal inertia instead of double-flow ventilation or even air conditioning, or even swing or sliding shutters rather than electric roller shutters requiring maintenance and energy).
The sustainable city is more about taking needs into account than adding unsolicited solutions that are therefore often not understood.
The renovation will go through the Human for the Human.
An article by Arnaud ALAVANT, Chairman of Aedificem and Aymeric THOMAS, Manager of Moebius Développement
 On this subject, see the interesting thesis by Yasmina Dris (2021), which raises the question of consultation as the main point of divergence between planners, some of whom make it an essential and unavoidable step in an architectural programming process, and others doconsidering it only as a tool for gathering needs.
 On this subject, see the recent book Démarches de programmation architecturales (coordinated by E. Redoutey and G. Pinot), Éditions du Moniteur, 2021.
A DOSSIER CREATED WITH THE SUPPORT OF: