The building through the restructuring has been transformed from a hotel into a residential building with 6 apartments.
The building in question is composed of 5 floors with a traditional construction type: the supporting structure is a reinforced concrete frame, with a brick infill. The energy redevelopment was obtained with a 10 cm insulation on the external walls, 14 cm on the roof, 10 cm on the floor against the ground, with the replacement of the existing windows and boxes with appropriate products and with the modernization of the ‘heating system.
Particular attention has been paid to the elimination of thermal bridges as provided for by the CasaClima Technical Directive, given that to be a CasaClima it is not enough to achieve a certain Energy Class but it is also essential to achieve a certain standard of construction quality without which certification cannot be obtained. . A careful study of the construction details was necessary to solve all the thermal bridges. To avoid the problem of summer overheating of the rooms, the thermal phase shift verification (greater than 10h) and periodic transmittance (less than 0.10W / mqK) was carried out. In addition to the traditional checks, it was necessary to carry out, in the critical nodes, the study of isotherms and minimum temperatures with a Finite Element Software, for the checks related to the formation of condensate or molds.
The building, like most of the existing houses, had a high energy consumption for heating equal to 150 Kwh / m²a (Class F). Through energy requalification consumption fell to 30 kWh / m²a (Class A).
On balance the savings you get are 120 Kwh / m²a which multiplied by the total area of 600 m² amounts to 72,000 Kwh / year; translated into euros, around € 7,000 is saved each year (ie around € 1100 per apartment each year).
If tax incentives are taken into account for 55% deductions on energy requalification works, the money spent at the start is largely amortized over the short term (4.5 years). In addition to the savings in the bill, there are other benefits: a high living comfort, the increasing economic value of this type of housing over time and the respect of the Environment obtained through the reduction of CO2 Emissions, in this case 20 tons of emissions in less CO2 per year.