Thermal resistivity of duct material

According to standard IEC 60287-2-1 Ed.2.0 with exception to metal, where the thermal conductivity of wrought iron/steel with a value of 59 W/(m.K) is taken instead.

Symbol
$\rho_d$
Unit
K.m/W
Choices
MaterialValue
PE3.5
PP4.5
PVC6.0
WPE3.5
Metal0.017
Fibre4.8
Earth1.2
Cem2.0