Steel Building Foundation Options
Steel buildings require some kind of foundation/footers on which to anchor the columns to give the structure strength and stability. The foundation is definitely the most important part of the steel building project, which should not be underestimated. In fact, the construction of a steel building is similar to the construction of most buildings – it starts with a strong foundation.
Most commercial and industrial steel buildings require concrete slabs while some agricultural steel buildings use concrete piers instead of a full slab. Whatever foundation is used, it is advisable to hire a foundation engineer to do the design and construction. The metal building supplier is not responsible for the foundation’s design. Upon placing the order, the contract documents that are provided include erection drawings. They are actually anchor bolt plans that show the location, diameter, and projection of the bolts that will be attached to the foundation.
In general, there are two types of foundation that are used for pre engineered steel buildings – the portable foundation and the permanent foundation. However, there are many variations under each category.
As the name implies, a portable foundation is generally used for portable steel building applications like cabins. A portable foundation may not be as strong as a permanent foundation but it is still sturdy enough to hold the metal structure. The steel building is assembled on top of an industrial plate that is in turn, connected to a concrete perimeter by anchor bolts. The most important advantage of a portable foundation is that it allows the building to be moved to another location. Another advantage is that the height of the building is also retained. In addition, building a portable foundation is much simpler and requires less time when compared to a permanent foundation.
Permanent foundations are for steel buildings that do not need to be moved, like houses and industrial applications. Usually, these structures have higher loads. That’s why a permanent foundation is more suitable.
COMMON FOUNDATION TYPES
A floating slab foundation or a floating foundation is a concrete slab with a continuous grade beam. Continuous grade beams carry the vertical load of the columns. The concrete is spread directly under a column or reinforced along the bottom.
Another type of foundation uses piers, footings, and grade beams. The foundation consists of square or rectangular footings and grade beam walls. Sometimes, a driller pier is used in place of the footing. Overall, the piers and footings carry most of the vertical loads of the steel building.
No matter which foundation is used, the site for the steel building must first be surveyed and marked by a professional, before leveling and excavation can begin. Surveying involves marking the exact boundaries of the plot. The surveyor makes sure that the construction site is level. The land must also be physically leveled or graded. This ensures that it conforms to the height and shape of the surveyor’s stakes. After this process, excavation can begin and the construction of the foundation of the steel building can commence.