The antiseismic renovation of an existing building can affect any element that needs to be secured, from the foundations to the floors, from the walls to the roof. To improve a building from an earthquake protection point of view and make it resistant if an earthquake strikes, there are several interventions that can be implemented. The work required depend on the condition of the building and can be minimally invasive or require more substantial renovations, especially in case of renovations of condominiums that are a few decades old. Especially in an earthquake-prone country such as Italy, carrying out the appropriate interventions according to current regulations is essential for limiting damage to structures and injuries to people during the ground movement event. Let us now see how we can make a building earthquake-resistant.
What earthquake-resistant interventions can be carried out?
In general, antiseismic building interventions are intended to improve the structural safety of existing buildings, with works that may concern the whole building or a part of it (such as some particularly damaged areas or damaged structural elements). The interventions to be implemented vary from one structure to another, since the way to make a reinforced concrete building earthquake-resistant is very different from the technique used for a steel or stone building. For a detached house, it is easy to freely decide which elements to intervene on and in what way, since you can choose to demolish and rebuild the house or simply renovate it. The decision on the way make a condominium earthquake-resistant is different, as a resolution of the joint owners’ meeting is necessary. The key principles an effective seismic improvement is based on are inspired by Japanese antiseismic construction and the standards to be observed during the construction of new buildings, which are installation of seismic protection devices (both active and passive), choice of materials based on weight and characteristics and use of tremor-resistant elements. In light of this, let’s find out what particular interventions can be carried out, from the foundations to the roof.
Antiseismic renovation of perimeter walls and interior walls
Let us start with the foundations. How can we intervene on this element at the base of the construction? Consolidating the foundations is important to ensure the structure’s stability. After a ground analysis, these interventions can be carried out by injecting special material or by inserting reinforcing elements.
To ensure that the house is even more resistant if an earthquake strikes, we can install seismic isolators, passive devices that decouple ground motion from the superstructure, which absorb some of the seismic energy and limit the building’s movement. What about the floors? An intervention can be made on floors by making the support surface more solid and installing expansion joints that allow minimal movements to the structure without major damage.
Antiseismic renovation of perimeter walls and interior walls
Perimeter walls and interior walls are other important factors to take into account in antiseismic renovation work. It is possible to intervene with deep injection of reinforcing materials, which remedy the possible damage caused by time (such as cracks and obvious deteriorations). In addition, structural reinforcements can be inserted at critical points, preferring those made of carbon fibre, which are particularly light, adaptable and resistant.
An alternative, to be evaluated according to the type of structure, is to use methods to hold the walls together, such as steel bars, tie rods, chains or reinforced plaster. The insertion or replacement of antiseismic joints and the installation of passive earthquake dampers in certain points of the structure are other elements that can increase the building’s stability.
What about the roof? Antiseismic interventions to be implemented
The last, but not least, element to be included to improve earthquake resistance is the roof. The main characteristic it must have to resist an earthquake is lightness, because a lightweight roof does not weigh down on the walls or the rest of the structure and is less likely to collapse during earthquakes. How can the roof be made lighter? For the roofing of buildings we can choose wood, perhaps by inserting a structure of beams made of this material. In case of a reinforced concrete roof, it is important to check that there is a perimeter curb.
Costs and deductions for antiseismic renovation
Having reviewed all the antiseismic interventions that we can carry out, how much does the renovation of a building cost? Depending on the work required and the technologies used, making an existing building earthquake-resistant can be expensive, time-consuming and require evacuation of the building. We can reduce the economic impact of making a building earthquake resistant, by taking advantage of the Super Sismabonus 110% deduction, which allows us to renovate buildings practically at no cost.
ISAAC’s active system for making buildings earthquake-resistant
The facility also includes smart building protection systems, such as active antiseismic devices. This technology is installed directly on the building’s roof and is ideal for those who want minimally invasive, rapid and cost-effective antiseismic interventions. To ensure that the intervention is as effective as can be, before installation, through special simulations, our technicians verify how many devices are necessary and where on the roof they must be installed. In this way, the best configuration is obtained for each structure and the seismic protection provided by ISAAC systems is increased.
