ZEMCH 2015 - International Conference Proceedings | Page 592
Figure 7: Scheme of application of the insulating panel from the inner face of the wall.
The most appropriate strategies, planning to act from the internal part of the walls with the application the insulating material, take into account the following panels, selected as the most
common on the building market:
• Rock wool: λ = 0.040 W/m2K;
• EPS (Expanded Polystyrene Sintered) with conductivity value equal to λ = 0.033 W/m2K);
• Wood fiber panel (λ = 0.041 W/m2K);
• Opuntia ficus-indica panel (λ = 0.071 W/m2K);
• Air cavity (λ = 0.026 W/m2K).
Assuming, for each case, the application of a rigid panel of insulating material of 60 mm, it is possible to get the following values, as in Table 3:
Table 3: Thermal characteristic allowed by each strategy of thermal insulation.
CHARACTERISTICS:
CURRENT
STATE
AIR
ROCK WOOL EPS PANEL WOOD FIBER OPUNTIA
LIMIT VALPANEL
PANEL
FICUS-INDICA
UES
PANEL
FOR LAW
Wall thickness [mm]
250
250
310
310
310
310
-
Thermal trasmittance
U [W/m2K]
0.67
0.20
0.23
0.22
0.24
0.30
<0.48
Surface mass
Ms [kg/m2]
255
255
282
268
315
293
>230
Periodic thermal
transmittance
Yie [W/m2K]
1,51
0,07
0,02
0,02
0,01
0,03
<0.12
The panel of Opuntia ficus-indica, as reported in the table, has met all the legal limit values for
each characteristic indicative of the thermal performance of the envelope. The comparison of
these results with those obtained with other typologies of insulation panels, shows how the pan-
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ZEMCH 2015 | International Conference | Bari - Lecce, Italy