A roof has a U value = 0.65 W/m2 .C.
Extra insulation is to be provided. This insulation has a
thermal resistance =
1.5 m2"C/W.
Calculate the new improved U value.



A roof has a U value = 0.65 W/m2 .C. Extra insulation is to be provided. This insulation has a th..

Answer / Sarvesh Kumar Prajapati

To find the new improved U value, you can use the following formula: 1 / (U_old * R_new + R_old) where U_old is the original U-value, R_old is the thermal resistance of the roof without insulation, and R_new is the thermal resistance of the added insulation.nFirst, we need to convert the given thermal resistance from m2·°C/W to m·K/W because the U-value is in W/m²·K. 1 m2·°C/W equals 10 m·K/W. So R_new = 1.5 m2·°C/W = 15 m·K/W.nThen, since we don't have the original U-value and thermal resistance of the roof without insulation, let's assume that the initial thermal resistance of the roof is 0.4 m²·°C/W (a typical value for roof insulation).nUsing the formula, the new improved U-value would be: 1 / (0.65 W/m²·K * 15 m·K/W + 0.4 m²·°C/W) = 0.32 W/m²·K

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