Paper column forms, aka sonotubes, are an alternative method for concrete column forming. Columns are fabricated using a reinforced shaping structure, and traditionally steel or fiberglass was used in the process. However, those materials are both heavy and inflexible and require careful treatment. When fiberglass or steel column supports are used, the number of columns poured is limited to the equipment on hand. Paper column forms however are disposable and do not need to be reused, they also do not need added exterior support as fiberglass and steel tubes do. Therefore, the overall construction time is drastically reduced as multiple tubes are able to be poured simultaneously. They are also recyclable. Once the concrete column has set in the paper tube cavity, the outer cardboard layer can be removed and disposed of. They are typically made from biodegradable paper and so depending on the intended use of the column, can be left on or removed whole or in pieces. The pouring of the concrete is fairly straightforward, although for the longer columns, extra machinery may be required to ensure proper placement of the concrete.