What are column loads and why are they important for your floor?

When installing a mezzanine floor in your warehouse, workshop or production facility, there is more to consider than you might initially think. One of the most important aspects is the column load. In this blog, we explain in an accessible way what column loads are, which factors determine them, and what Anera can do for you.

What are column loads?

A column load is a local load on the floor on which the mezzanine floor is placed. This load consists of the weight of the construction, including everything that is placed on top of it. To ensure that the mezzanine remains stable, it is equipped with bracing elements. These locally create an additional column load.
You can compare it to a table resting on sturdy legs: everything you put on the table is ultimately carried by those legs – the columns.

Which factors influence column loads?

There are three key factors that determine the final load per column:

• Load-bearing capacity of the floor
  How much weight will be placed on the floor? Think of goods, workstations, machines, or traffic.
• Number of levels
  In multi-level setups, the weight of the upper floors is also transferred to the columns below.
• Grid size
  This is the spacing between the columns. A smaller grid (e.g. 3x3 meters) means more columns supporting the floor and therefore lower loads per column. A larger grid means fewer columns and therefore higher point loads.

Subfloors and floor types: what is possible?

Column loads are closely linked to the subfloor on which the mezzanine floor is placed. Not every subfloor is automatically suitable for heavy loads. An overview:

• Concrete floor
  The most common subfloor. Note: not every concrete floor has the same load-bearing capacity. The strength depends on the concrete mix, thickness, reinforcement, and execution. Anera can only provide information about the column load, not about the floor itself, unless this is supported by documentation from a certified party.
• Stelcon slabs
  When placing on Stelcon slabs, larger baseplates are often used and the area under the plate is “grouted” with concrete to eliminate height differences.
• Asphalt
  A softer subfloor. To better distribute the load, we advise using smaller grids (columns closer together).
• Tiles
  Not suitable as a subfloor. Our advice: first create a new foundation before the floor can be installed.

Does a larger baseplate help?

A common question is whether a larger baseplate reduces the column load. The answer: the column load itself remains the same, because the total weight does not change.
What does change is the pressure distribution on the subfloor. A larger baseplate distributes the weight over a larger surface, which can make a difference especially with weaker subfloors. It can therefore contribute to stability, but it is no replacement for proper calculation or structural adjustment.

Column types: depending on load and grid size

Anera supplies different types of columns, with variations in size and thickness (for example, box columns or H-/I-profiles). The right choice depends on:

• The weight on the floor
• The grid size
• The number of levels
• The height of the column
• The choice for bracing

The heavier the floor and the greater the distance between the columns, the stronger the columns must be. This is always calculated per project.
Note: the right column is never chosen at random, but follows from a calculation based on your specific requirements and technical conditions.

Why often only two anchors per column?

You may have noticed: during assembly, often only two anchors per baseplate are used instead of four. This is because in many cases columns are only subjected to vertical compressive forces, not to lateral or shear forces.
Therefore, two anchors are sufficient in these situations. For elements such as bracing – where inclined (shear) forces or tensile forces are involved – four anchors are used.
Important: this design principle only applies when the situation has been properly calculated. Other structures or countries may follow different standards.

What can Anera do for you?

Anera is happy to think along with you. Based on your specifications (such as desired floor load, floor dimensions and layout), we can use a calculation sheet to provide insight into:

• Which grid size fits your load requirements
• Which columns are required
• What this means for the column loads

Do you need a permit application? Then we can prepare a complete structural calculation, suitable for submission to municipalities, including:

• Loads on floor and columns
• Column positions
• Specifications of beams and bracing

Different regulations per country

Anera supplies in multiple countries, including Germany. Each country has its own calculation rules and safety standards. In Germany, for example, stricter standards apply to floor loads. That’s why we always check what is legally allowed in each country and adjust our calculations and recommendations accordingly.

In summary

Column loads are an essential part of a safe and stable mezzanine floor. By considering floor loads, subfloor and grid size in advance, you can avoid unpleasant surprises. The load-bearing capacity of the subfloor is decisive for the final design choices of a logistics mezzanine. Anera is happy to assist you with technical advice, calculation tools, and insights into regulations.
Want to know more or need advice about your situation? Feel free to contact us.