Racking can be found in almost every manufacturing and warehouse operation and in some retail businesses as well. Having observed several situations where racking was modified on site, it is fair to say that some of the modifications were less than acceptable.
On-site racking modifications are sometimes needed and, in this article, they will be discussed and some guidelines provided so that, if you are faced with a situation which indicates that racking modifications are needed, you might consider your options and make better decisions.
One of the most peculiar racking modifications ever witnessed was the modification of standard selective steel racks with the use of custom-fabricated “rack components” made out of wood, such as “two-by-fours”. These custom-fabricated “rack components” included frame extensions.
It was a bit of a mystery as to why it would have been necessary to fabricate wooden rack components when standard steel racking components are readily available. Who knows what circumstances caused that type of racking modification to be considered; it might have been a situation where someone was not aware of the available options, or how to source compatible racking components.
Let us look at some of the issues related to this particular situation. What is wrong with the above mentioned on-site modification of roll-formed steel racks? There are at least a few things that are not right.
First, no one could produce a document that indicated the load capacities of the custom-fabricated wooden rack components. The custom components were not designed, built and installed in accordance with any engineering standards or specifications.
Second, installation of custom-built wooden frame extensions on to existing steel upright frames altered the structural integrity of the existing racking. What it means is that the existing racks no longer met the original manufacturer’s specifications related to load capacities.
Third, in the unfortunate event of an accident, the manufacturer and/or supplier of the original steel racking would most likely not be held liable, because the racks were modified in a way that was not recommended by the manufacturer, or validated by an engineer.
Question: In the above scenario, where upright frame extensions were needed, what might have been some viable options to consider, other than fabricating and installing wooden frame extensions?
Note that in some situations, upright frame extensions are needed in order to take advantage of available overhead clearance. And, in other situations, upright frame extensions might be installed at the ends of rows, in order to help reduce the likelihood of objects falling into adjacent aisles.
In any event, regardless of the reason why taller upright frames are needed, a couple of better options for handling the frame extension scenario are as follows.
One option is to purchase steel frame extensions, built by the manufacturer of the original racking. If a large number of frame extensions are needed, it might be cost effective to purchase them. However, if only a small number of frame extensions are needed, the cost might be prohibitive.
If only a small number of frame extensions are needed, a second option is to replace the existing upright frames with new frames that are taller than the existing ones.
Okay, let’s change gears. The following is a more successful racking modification and a good example of how to get on-site racking modifications done.
In this example, some on-site racking modifications were required for a very large installation of structural steel racking in a distribution center, which was an empty facility that the company was moving into.
Used structural steel racking was purchased and, knowing that there would be a need for a Pre-Start Health and Safety Review, the company contracted with us, just prior to start of installation of the storage racks.
The racking components were in very good condition. However, based on the configuration of the proposed installation, i.e., single rows, back-to-back rows, and the number of beam levels and vertical spacing between beam levels, load capacities were determined. These load capacities were then compared with proposed maximum loads that were to be placed on the storage racks, in order to verify adequacy of the storage racks for the intended use.
As might be expected in this type of situation, some on-site racking modifications were needed. In the case of the single rows of racks, cross-aisle ties were needed for stability. These custom components would not have been available for purchase as used equipment. So, they were fabricated to suit the particular installation.
In addition, it was found that base-plates of the upright frames were not thick enough for the single rows of racks. As such, on-site modifications were needed in order to stiffen the base-plates, and additional anchoring procedures were specified.
Fortunately, all of the modifications were done at the time of installation of these racks. Would it have been necessary to have an installation crew visit the site with welding equipment and tools, specifically for the purpose of performing on-site racking modifications, it would have been much more costly.
As a point of information, the following are a couple of rules to keep in mind when installing used racking in your facility.
The first rule is to not assume that the previously rated load capacities, shown on load capacity labels of used racking, are applicable to your racking installation. Why not? Your racking configuration might be very different from that of the previous owner.
The second rule is to have the installation validated by an independent engineer. Generally, the earlier that an independent engineer gets involved in the planning and installation process, the better it is from the perspective of getting the job done right, and at minimum cost.
On-site racking modifications are sometimes unavoidable. However, it is definitely an undertaking that requires careful consideration and engineering due diligence.
Jack Jagernauth, P.Eng. is a project engineer with Rack Inspections Ontario, an engineering company providing services related to racking safety, racking inspections and PSRs. He may be reached at 905-847-3640 or jack@rackinspectionsontario.ca, or through the company website: www.rackinspectionsontario.ca.