Steel siding is a popular siding choice with those who want more durability and improved maintenance demands than vinyl siding. Steel siding being more rigid can lay straighter than vinyl and is less likely to bend or buckle during expansion and contraction. There are many styles of steel siding which mimic wood or plastic siding products like clapboard, Dutch Lap, Board and Batten, etc.
In some cases steel siding can be placed over existing siding depending on condition of siding and type. Wood siding can be a substrate if it’s in good condition and not rotted.
Plastic siding however typically does not make a good substrate for steel siding. Steel siding often comes new with a baked on PVC coating but can be painted over as well if a different color is desired down the road.
In terms of upfront cost, steel siding is often not competitive with most standard vinyl sidings, but is similar in price to most high end vinyl and also cement board and is argued to be more long lasting than many plastic sidings.