$=0\mathrm{.}12m^2\frac{K}{W},$ still air$).$ Eight clear, double$-$pane $(6\mathrm{.}4$ mm with U$-$factor of $3\mathrm{.}56\frac{W}{m^2}.K)$

windows are mounted in Aluminium frames with each window $1\mathrm{.}2m1\mathrm{.}5m$ high. The

roof is flat $($type $3),13\mathrm{.}7m18\mathrm{.}3m$ constructed of $100$ mm lightweight concrete

$($:$0\mathrm{.}54m^2\frac{K}{W}\}$ with $90$ mm insulation $)=(2\mathrm{.}29m^2\frac{K}{W},$ steel decking $,$

no dimension given$)$ and the built$-$up roofing with $)=(0\mathrm{.}06m^2\frac{K}{W}.$ Additionally, there

is air film on the outside of the wall $)=(0\mathrm{.}25m^2\frac{K}{W}$ moving at $12k\frac{m}{h}$ during the

summer and another air film on the inside surface of the wall $,$ still

air$).$ Using the CLTD tables for sunlit walls and flat roofs for $26$ South Latitude,

calculate:

$2\mathrm{.}1$ the U$-$factor of the wall and of the roof, respectively

$2\mathrm{.}2$ the conduction through the sunlit surfaces