PPGL or pre-painted galvalume steel, on the other hand, is coated with a mix of aluminum, zinc and other trace elements. The usual composition of galvalume coating is 55% aluminum, 43.4% zinc and 1.6% trace elements.
Attributed to the difference in their coatings, PPGI and PPGL steel consequently vary in their properties as well.
1. PPGL steel offers a smoother finish than pre-painted galvanized steel.
2. Corrosion in PPGL steel spreads, whereas in PPGI steel it remains localized and do not
3. PPGL steel is more corrosion resistant than PPGI steel, however, its cut edges are less
protected. This is because of the steel coating’s honeycomb structure, which does not provide sufficient protection to exposed edges.