Nautically, a flat timber or metal ledge projecting from the hull vessel above the chain plates to the angle of the shrouds. Channel Bar is rolled steel, an iron having a U shape cross section with two narrow sides at right angles to a broader one.
Chanel bars are used for the structure or foundation; they serve as the skeleton and the major support for a building. These are also known as heavy duty purlins since they are used for large constructions.