Heavy wrought-iron pipe is often used for columns, a cap and base being sometimes cast and screwed on by a thread; and a patented column formed by filling the pipe with cement, may be obtained ready fitted with cap and base.

Steel Columns and Girders, Where the spacing of columns is required to be increased beyond the safe bearing of wooden girders, steel girders may be used. These usually consist of one or more steel I-beams, and they may be used with cast-iron columns or with steel columns. With cast-iron columns, the same methods will suffice as in the use of wooden girders, but with the use of steel columns a new method of construction arises, which it will be better to consider later in connection with steel framing. It may be properly said here, however, that the use of steel girders and steel columns, even if the floor timbers are of wood, is to be recommended for high buildings or for buildings which are subjected to the jar of machinery; the reason for this being in the greater rigidity which is possible in the girder and column connections, and the greater ease with which this construction can be braced.