Question: how to calculate insulation thickness for ducts?
Answer: General Formula to Calculate Minimum Insulation Thickness Required to Prevent Condensation,t= k * R{(T1 - T2)/ (T3 - T1)} , Where, t = Insulation thickness (in) k = Thermal conductivity. R = Surface temperature resistance. T1 = Dew point temperature (°F) T2 = Operating temperature (°F)