Building Renovation and Sustainability

Sustainable building recovery currently represents a among the most relevant challenges for architects, engineers and designers, who find themselves operating in a context in which natural resources are increasingly limited and the environmental impact of construction continues to be significant.

Redevelop instead of demolish Today, it is not only an ethical choice, but also a strategic one, as the reuse of existing structures allows for reducing land consumption, preserving the historical and cultural memory of places, and, at the same time, improving comfort, efficiency, and the quality of spaces.

Let's see below what there is to know about building recovery with a view to sustainable redevelopment, with an analysis of the phases, the best technical solutions and the design criteria, and with some concrete examples of recovery interventions without demolition.

Sustainable building renovation: preliminary diagnosis required

The starting point for any building renovation project is a complete diagnosis e multidisciplinary of the existing building.

It is not just a matter of evaluating the static or system conditions, but of adopting an integrated approach that includes:

Structural analysis, with evaluation of resistance, material degradation and seismic vulnerability;
Energy analysis through thermography, dynamic simulations and BIM models, in order to identify heat dispersion and inefficiencies;
Hygrometric and acoustic analysis, essential for interior comfort and durability;
Historical-architectural evaluation, in order to understand the cultural value and typological characteristics to be safeguarded.

Today tools like theHBIM (Heritage Building Information Modeling) allow you to integrate geometric, material and energy data into a single model, thus facilitating targeted and verifiable choices.

A well-conducted diagnosis reduces economic and environmental waste, because it allows concentrate interventions where they are really needed.

Building envelope and passive strategies: the heart of building renovation

The envelope represents the most energy-intensive and delicate part of a building, therefore, the main challenge in the field of building renovation is to succeed in improve its performance without distorting the structure existing.

The most adopted solutions include:

High performance outer or inner coats, designed to suit the original materials and the breathability of the walls;
Replacement or restoration of windows and doors, favoring low-emissivity glass and thermal break frames compatible with the aesthetics of the building;
Natural ventilation and hybrid systems, which reduce energy requirements without visual impacts;
Integrated shading solutions, such as mobile sunshades or climbing vegetation, which improve the summer microclimate.

When working on historic buildings, it is not always possible to install external insulation or make changes to the facades.

In that case, therefore, certain measures are more effective (and feasible). interventions that are invisible but effective, such as internal insulation in natural materials (hemp, lime, cork) or the use of low-emission glass coupled with the restored original windows.

The guiding principle remains that of passive strategies: exploiting orientation, thermal inertia and ventilation to minimize the use of mechanical systems.

Also read: "Nature in architecture: the built environment dresses in green"

Plant technologies and a “soft” approach

In a sustainable building renovation project, the plant engineering aspect cannot be overlooked. Here too, however, it is essential that theintegration of technological systems occurs discreetly, and without altering the existing structure.

From this perspective, there are several solutions that can be taken into consideration, such as:

Air-to-water or geothermal heat pumps, combined with radiant panels that guarantee comfort with low operating temperatures;
Integrated photovoltaic in roofs or canopies, avoiding aesthetic impacts and favouring low-reflection modules;
Water recovery rainwater for irrigation or secondary uses, in order to reduce water consumption;
Home automation systems for real-time consumption monitoring and intelligent system management.

The “soft” approach that needs to be adopted essentially implies the introduction of new technologies without forcing them, favoring reversibility and compatibility with the context.

The aim is to guarantee high performance, but with building recovery interventions that aim first and foremost to respect the integrity of the building.

Life Cycle Thinking approach and safety

Sustainability is not only measured by the reduction of energy consumption, but must be understood as a much more extensive methodological system, which is able to take into account the entire life cycle of the building.

The Life Cycle Thinking approach (LCT) requires evaluating each design choice in terms of overall environmental impact: material production, transportation, installation, maintenance and disposal.

In this sense, local and natural materials take on strategic value, not only because they reduce the ecological footprint, but also because they can improve the healthiness of the environment.

At the same time, it is essential integrate the issue of seismic safety with the energy issue: consolidation and structural reinforcement interventions can be combined with coats or cladding, thus reducing both costs and impacts.

Building recovery must therefore pursue long-term resilience, with buildings capable of guaranteeing safety, comfort and low consumption. throughout their life cycle.

Practical cases of sustainable building renovation

Several projects already completed in Italy clearly show the potential and advantages of interventions sustainable building recovery without demolition.

Some of the more well-known examples include:

Former Prison “Le Murate” in Florence: transformed into a residential and cultural complex, it has maintained its historical memory and integrated new functions with minimally invasive interventionsAwarded in the 2012 edition of the Gubbio Prize, is an example of how building recovery can also become a tool for urban regeneration;

“Villa Agor Eco Residence” In Cuneo: a project that involved the redevelopment of abandoned mountain structures, focusing on natural materials (hemp, cork, wood) and renewable energy systems.
It is the The first project in Italy to combine intergenerational cohousing, passive housing, and the recovery of abandoned mountain structures. in a replicable model of passive and social housing;

Condominium “25 Verde” in Turin: although it is not a building recovery project but a new construction, it is the first experiment in eco-sustainable bioarchitecture carried out in the city, conceived as a habitable forest, in which 63 apartments are surrounded by nearly 200 plants. It demonstrates how integrated greenery can become an element of comfort and sustainability, suggesting solutions also applicable to existing buildings (green facades, vegetated terraces).

These examples confirm how redevelopment, if well-designed, can generate environmental, social, and cultural value, avoiding demolition and waste.

Design guidelines and useful tips

Experience and best practices have revealed some valid principles that can be useful for any building renovation project that does not involve (or partially involves) the demolition of the existing structure.

It is particularly recommended:

Minimize demolition, to conserve as much of the existing structures as possible;
Designing reversibility, as each intervention should be able to be modified or removed without compromising the building;
Integrating greenery and microclimates, with Hanging gardens, green facades and internal courtyards that improve comfort and air quality;
Leveraging functional flexibility, because spaces already designed for possible changes in intended use reduce the need for future interventions;
Using simulations and digital models, with BIM tools and thermal simulations that enable accurate performance predictions;
Engaging users and communities, as a renovated building becomes truly sustainable when it responds to the needs of those who live in it.

We can therefore say that a redevelopment project without demolition must be able to combine 4 essential factors: tradition, innovation, sustainability and identity.

For students and professionals, building renovation today represents a fertile ground for experimentation and creativity, in which technical knowledge must necessarily intersect with environmental sensitivity.

Sustainable redevelopment is in fact no longer an option, but is the essential condition on which the future is built.architecture of the present and the future.

The author of the cover photo is Vita Popova on Depositphotos.com