Question $1(20$ marks$)$

Using the information contained in Figure Q$1$ and in accordance with Technical Guidance Document $($TGD$)$ Part L of the Building Regulations, calculate the overall U$-$Value $($W$/$m$^2$K$)$ of the timber$-$frame wall depicted in Figure Q$1,$ where one of the layers of insulation is thermally bridged.

$\backslash$table$[[\backslash$table$[[$Layer$!],[$Surface$]],\backslash$table$[[$Thickness$],[($m$)]],$Conductivity $($W$/$mK$),$Resistance $(m^{2}KW)],[$External surface,$-,-,0\mathrm{.}040],[$Brick outer leaf,$0\mathrm{.}102,0\mathrm{.}77,0\mathrm{.}132],[$Air cavity,$0\mathrm{.}012,0\mathrm{.}13,0\mathrm{.}180],[$Sheathing ply$,0\mathrm{.}012,0\mathrm{.}13,0\mathrm{.}092],[$Polyisocyanurate $($PIR$),0\mathrm{.}150,0\mathrm{.}023,6\mathrm{.}522],[$Timber studs,$0\mathrm{.}150,0\mathrm{.}12,1\mathrm{.}25],[$Plasterboard$,0\mathrm{.}013,0\mathrm{.}25,0\mathrm{.}052],[$Internal surface,$,.,0\mathrm{.}130]]$

$\backslash$table$[[\backslash$table$[[$Timber fractions for bridged$],[$layers$]]],[\backslash$table$[[$Layer$,\backslash$table$[[$Timber$],[$frame$],[$walls$]],\backslash$table$[[$Celing$],[$flatsloped$]],\backslash$table$[[$Drylined$],[$battened$],[$wall$]],\backslash$table$[[$Suspended$],[$timber floor$]]],[\backslash$table$[[\%$