In a context of climate challenges, societal changes, diversity of use and increasing needs – can public buildings still be renovated as they were in the past ?
The renovation of public buildings has now emerged as an important means of responding to changing uses and occupant well-being. Its focuses include energy efficiency, climate change and scarcity of resources.
From hospitals to town halls, schools and administrative centers – public buildings come in many forms and have a wide range of uses. Since they are expected to last over time, however, most of these buildings require large-scale investments in order to adapt to new economic, ecological and societal challenges.
The first challenge to be addressed is the reduction in consumption, as part of a sustainable development approach. Many of these buildings leak energy and have a high carbon footprint, weighing heavily on municipal budgets. The reason is simple: in the past, buildings were not constructed according to the same thermal rules as today. As a result, many schools – to take just one example – are still encased in old concrete structures, as well as being poorly insulated.
Comfort and quality of use
While there is an urgent need to step up the energy transition, that is just the tip of the iceberg. “A renovation project is not about energy efficiency alone,” says Olivier Servant, Director of Saint-Gobain Solutions France. “It needs careful consideration in advance in order to offer optimal comfort and quality of use.” Let's return to the example of schools which, as well as being energy-intensive for municipalities, also offer sub-optimal conditions for teaching. Drafty in winter, ovens in the summer, neon-lit and noisy... whereas it has been proven that students learn better when they are in a healthy environment, with good acoustic comfort and natural lighting. The same is true in hospitals. Studies show that patients recover better and faster in a room with a constant temperature (around 23°C), flooded with natural light.
Energy renovation must therefore be approached from several perspectives. As well as thermal comfort, environmental quality will also determine the solutions to be favored within the framework of a renovation. For a hospital, for example, it would appear advisable to use windows with solar control and enhanced insulation, equipped with extra-clear glazing to allow light to pass through. In view of the current health crisis, future renovations should also incorporate the risk of epidemics, with efficient ventilation systems and a choice of biocidal surfaces.
“Renovation of public buildings should also take a long-term perspective,” says Olivier Servant. Overall, a construction has a lifespan of 100 years, with a renovation at around 50 years. It is important to consider future challenges today, taking into account the adaptability of uses and modularity of spaces. ” Will this building be able to increase its capacity? Will it be able to accommodate new services? Will the space be easy to convert? To take a forward-looking approach, we need to anticipate future uses. That is particularly the case for the Saint-Joseph Hospital in Paris which, as part of an extension, has opted for ISOVER F4 facades. This removable cladding will facilitate future expansion projects.
Scarcity of raw materials
Taking a long-term approach also means taking into account the scarcity of materials and considering public buildings throughout their life cycle, right up to demolition.
From the use of biobased products to materials that are recycled and from renewable resources, the modernization of public buildings aims above all to be sustainable and responsible. But the story does not end there. The renovation must also focus on a “passive” and bioclimatic design of buildings, in order to optimize management of daylight and natural ventilation.
And what about climate change in all of this? That is an important question, since public buildings have some catching up to do in terms of their impact and the adaptations that will need to be made in terms of thermal regulation, earthquake-resistant materials, hurricane-proof construction, resistance to humidity, etc.
Public buildings of the future will be resilient
So what will public buildings of the future actually look like? Truly polyvalent, they will be modular, hybrid and energy efficient. Positive-energy public buildings will be both smart and connected, managing their resources independently and operating with complete autonomy. Able to be entirely dismantled, they will be designed from biobased, recycled, recyclable – and even re-used! – materials.
The idea of refurbishing certain products (e.g. doors and locks) is also becoming more popular. A few decades from now, we may even see new sectors emerging with databases of entirely refurbished materials, as with cell phones now!
Photos credits: Peter Milto / Shutterstock, Anna Brothankova / Shutterstock