The issue of dissimilar metals and galvanic corrosion is a key concern for metal roofing in the highly corrosive Singaporean atmosphere; a professional contractor must ensure that copper flashings or fasteners, for example, are never placed in direct contact with an aluminum or Galvalume roof panel, as the electrochemical reaction would lead to rapid deterioration of the less noble me... https://kkroofspecialist.com.sg/metal-roofing-singapore/