Question

A wall consists of 100mm face brick, 200mm concrete block and interior plasterer, find the energy which can be saved if 50mm of fiber glass layer is added to the wall.​

Answer 1

To determine the energy saved by adding a layer of fiberglass to the wall, calculate the rate of heat conduction before and after the addition of insulation.

Step-by-step explanation:

The energy that can be saved by adding a 50mm layer of fiberglass to the wall can be determined by comparing the rates of heat conduction before and after the addition of the insulation. In this case, we need to consider the thermal conductivity of each layer of the wall and the new total thickness of the wall.

First, we can find the rate of heat conduction through the wall without the fiberglass layer. This can be calculated using the formula:

Q = (k * A * ΔT) / d

where Q is the rate of heat conduction, k is the thermal conductivity, A is the area, ΔT is the temperature difference, and d is the thickness of the wall.

After calculating the rate of heat conduction without the fiberglass layer, we can then calculate the rate of heat conduction with the added fiberglass layer using the same formula but with the new total thickness of the wall. The energy saved can be determined by subtracting the rate of heat conduction with the fiberglass layer from the rate of heat conduction without the fiberglass layer.