The process of re-roofing over an existing asphalt shingle roof, or a "roof-over," is a service expertly managed by a metal-roof-contractor. While possible with lightweight metal, it requires careful assessment by the metal-roof-contractor to ensure the existing structure can support the combined load and that the underlying shingles do not compromise the longevity of the new metal pa... https://kkroofspecialist.com.sg/metal-roof-contractor/