ZEMCH 2015 - International Conference Proceedings | Page 589

Figure 4: Cladodes of Opuntia ficus-indica
In order to realize a prototype of a rigid panel, suitable to the building envelope insulation, the
mixture obtained was tied using as adhesive a polyester resin so as to obtain a compact layer
resistant (Figure 5) having specific weight of about 450 kg/m3.

Figure 5: Final product: the Opuntia ficus-indica rigid panel

Application of the insulating panels into an existing dwelling
In order to evaluate the thermal efficiency of new panels Opuntia ficus-indica, it is necessary to
verify the possibilities of use, by comparing the benefits achievable through other panels most
common on the market.
The comparison was made on a selected case study, simulating their individual application to the
building envelope. the case study is an exemplar dwelling of the city of Palermo, in need of an
intervention to increase its energy performance, starting from the opaque external walls.

Methodology of action
The analysis takes into account the main thermal and dynamic characteristics of the envelope
that affect its energy performance, both during the cold and the warm seasons.
The improvement of the energy efficiency of the opaque walls, by the application of insulating
panels from the inside, means not only better U-value and lower conductivity of the walls, but
also it affects the analysis of the energy demand and, therefore, the annual energy costs of the
dwelling.

Eco-friendly materials for the energy retrofit of existing buildings

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