Chapter 5, Problem 5.16P

A wall is 20 ft (6.1 m) wide and 8 ft (2.4 m) high and has an overall heat-transfer coefficient of $\text{0}{\text{.07 Btu/(hr-ft}}^{\text{2}}\text{-F)}\text{.[0}{\text{.40W/(m}}^{\text{2}}\text{-C)]}$. It contains a solid urethane foam core steel door, $80\times 32\times 1\frac{3}{4}\text{in}\text{.}(203\times 81\times 2\text{cm})$, and a double glass window, $120\times 30\text{ in}\text{.}(305\times 76\text{ cm})$. The window is metal sash with no thermal break. Assuming parallel heat- flow paths for the wall, door, and window, find the overall thermal resistance and overall heat-transfer coefficient for the combination. Assume winter conditions.