A composite wall is made up of external thickness of brick 110mm thick inside which is a layer of fiberglass 75mm thick, the fiberglass is faced internally by an insulating board 25mm thick, the...

A composite wall is made up of external thickness of brick 110mm thick inside which is a layer of fiberglass 75mm thick, the fiberglass is faced internally by an insulating board 25mm thick, the coefficients of thermal conductivity of the three materials are, brick, 0.6w/mk, fiber, 0.04w/mk, insulating board, 0.06w/mk, the surface transfer coefficient of the inside wall is 2.5w/m^2k and that of the outside wall is 3.1w/m^2k, determine the overall heat transfer coefficient for the wall