Calculating Heat Loss Through Attic Insulation

Understanding Heat Loss Calculation:

The given data states that a 150 m² ranch house has glass fiber insulation 20 cm thick in the attic. The outside temperature is 0 °C, while the house is heated to 20 °C with a thermal conductivity of 0.042 J/(m*s*C). We need to calculate the heat loss per hour through the attic insulation.

Calculating Heat Loss:

To calculate the heat loss per hour through the attic insulation, we use the formula for heat transfer:

Heat loss per hour = (Thermal conductivity) * (Area) * (Temperature difference) / (Thickness)

Given values:

Thermal conductivity = 0.042 J/(m*s*C)

Area = 150 m²

Temperature difference = (20 C - 0 C) = 20 C

Thickness = 20 cm = 0.2 m

Plugging in the values:

Heat loss per hour = (0.042 J/(m*s*C)) * (150 m²) * (20 C) / (0.2 m) = 1260 J/h

Therefore, the heat loss per hour through the attic insulation is 1260 J/h. This means that 1260 joules of heat energy are lost every hour.