1) S I CAN INCREASE THE ENERGY CLASS OF AN OLD APARTMENT?
Even old buildings can achieve a conspicuous improvement in energy performance, and if we consider that in buildings built up to 1990 thermal insulation is almost non-existent, we can guess why today most of the houses are in class G, or at most, F, with great room for performance growth. The extent of the energy class improvement depends on the type of renovation / redevelopment interventions that are carried out. On the Energy Performance Certificate, the certifier lists some of the possible (although not immediately mandatory) interventions to improve energy efficiency: for example, insulation, adaptation of systems and the use of solar thermal.
2) HOW TO REACH ENERGY CLASS “A”
To reach class A starting from a low class (eg. G or F), it is not enough to improve the thermal insulation a little or slightly intervene on the heating system, but it is necessary to intervene heavily on several fronts. In practice, it is necessary to carry out at least two of the following interventions: (a) external insulation, eliminating thermal bridges, replacing the glass with triple glass; (2) replace the heating system with one with a heat pump and floor panels, or in any case at a low temperature; (3) produce energy with renewable sources. Of course, a professional will be able to indicate the most suitable interventions in your specific case and carry out the calculations to verify that the proposed solution actually allows you to reach the desired energy class. At that point, taking into account the cost of materials and labor, it will be possible to know the amount of the expense and evaluate the opportunity or not to carry out the restructuring / requalification interventions.
3) G LI IMPROVEMENT INTERVENTIONS ON THE BUILDING ENVELOPE
Energy class of a building is to intervene on the building envelope, which separates the exterior from the interior of the building itself. Older buildings mainly used materials with a high thermal transmittance, i.e. poor thermal insulation. These materials can therefore be replaced – or better integrated – by using insulating materials of suitable thickness, for example blown into the cavity or applied as internal or external coats. The latter represents the best solution, when practicable, given the totally enveloping character of the insulation thus obtained. Moreover, This category of interventions includes the replacement of single glazing with double or triple glazing with very low thermal transmittance, since windows usually represent one of the weak points of a building’s thermal insulation. The performance of the enclosure is defined by a class, ranging from I (the best) to V (the worst).