Blockhouse Bay of West Auckland roof painting job done in 5 days. Check the difference before and after the water blasting. The house is hidden in the bush. The color steel roof was cleaned completely, it took one guy a whole day.
Many different metals are used for roofing. Copper, which over time develops a signature green patina, is found in many older cities, especially on prominent ecclesiastical, university or government buildings. Tin roofs common on farm buildings are actually more likely to be corrugated galvanized steel. Other metal roofs are not always recognizable. Terne, which is steel coated with an alloy of tin and lead, is usually painted.
Some modern aluminum roofing is die-stamped to look like wood shingles, and some steel roofing panels are preformed to resemble clay tiles. Most metal roofing features some sort of contoured or formed edge that overlaps the edge of an adjacent piece to create a water-shedding joint. Corrugated panels simply overlap a crest and trough. Flat roofing panels have standing seams along their edges that are crimped tightly to connect them to each other. Copper ranks high in durability; properly installed, it can last a century under the right conditions. Other roofing metals are more subject to corrosion, but even aluminum and galvanized steel can last for decades. Salt air is very corrosive to metals, but a more common factor in metal roof failures is a destructive chemical reaction, called electrolysis, that occurs when dissimilar metals contact one another. For this reason, it’s very important to install metal roofing using fasteners made of the same metal.
Painted steel or terne roofs must be repainted and touched up to prevent rust. Pinhole leaks can be fixed with roofing cement or an asphalt-based sealant. Larger holes or tears can be mended by soldering on a patch of the same metal. Steel and terne should be soldered with a non-corrosive resin flux; copper should be soldered with acid flux. Aluminium roofing does not need to be painted, but it often is for aesthetic reasons. Fasteners are usually screws with sealing washers, as nails tend to loosen over time.