A domestic pitched roof of tiles on felt sacking with a plasterboard ceiling has an existing u-value of 1.9w/m2k. Calculate the minimum thickness of fibre glass insulation in the roof space required to give the roof a new u-value of 0.25w/m2k. The thermal conductivity of the fibre glass used is 0.04w/mk

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Conduction and Convection

When energy travels from one object to another it is said to have undergone heat transfer. Heat transfer is nothing but the transfer of thermal energy or internal energy from one thing to another, like e.g., when a vessel with water, kept on top of a burner, heats up because of the flame underneath it.