There are differences in their chemical composition, but the primary difference between cast iron and wrought iron is in how they’re produced: cast iron is iron that’s been melted, poured into a mold (i.e. a “cast”), and allowed to solidify into its current shape. Wrought iron, on the other hand, is iron that’s been heated and hammered with tools (i.e. “wrought,” the archaic past tense of “work”) to form it into a precise shape.
According to the regulations, from 2021 onwards, the Uw value of a vertical window must not exceed 0.9 W/(m2*K). However, it is worth mentioning that each of the two basic elements that make up a window, namely the frame and the glazing, have a different thermal transmittance. Consequently, the thermal transmittance of the glazing Ug is lower than that of the profile Uf, which makes the glazing a warmer window element. Uw is, in turn, only the resultant of the two values we mentioned.