High-density shelving systems require a floor loading analysis in storied facilities to ensure the floor can hold the weight of the system. Below is a description of floor loading and why this review is necessary.
Floor Loading Considerations:
There are two types of loads in high density shelving systems, live and dead. Live loads deal with the moving loads the footprint of the high density shelving system. Dead loads deals with the fixed weight of the high density shelving system footprint.
Most buildings have a minimum floor loading rating of 50 lbs per square foot. Floors designed for library system require a minimum of 100 lbs per square foot.
Most floors are not designed with high density shelving systems in mind and are usually not built to meet the loads required for a high density system. Because of this, floors require a floor loading review of the high density shelving system footprint before a system can be installed.
Floor loading is very commonly mistaken by dividing the square footage of the high density shelving system into the total weight of the system. Floor loading is much more complex and requires a certified structural engineer to provide a review of the floor and high density system for installation.
Loads on high density shelving systems are defined as point loads on the rails as the weight from the shelving, media and carriages is transferred to the wheels and from there to the slab and then the structure. This analysis shows that dividing the square footage into the system weight will not be sufficient as these systems have point load distribution and are not distributed throughout.
A high density shelving system layout with rail placement showing the center to center measurements is required for a structural analysis. The weight transfer between rail centers will vary per system.
Our local ASA members are experts in the design and implementation of high density shelving systems and will provide details with CAD Drawings, number of carriages and their dimensions, shelving dimensions and most importantly the amount of usable filing inches in the high density system. Media weight makes up the majority of the system and is crucial when calculating floor loading.
Working with ASA members, you will receive a formula showing the high density shelving system components and media weights separately. This formula will show how the media weights were calculated and the system weights.
In some cases the structural review of a high density shelving system allows for a complete installation with no modification to the floor. When the high density shelving system load exceeds that of the floor, there are options available to modify the floor for a high density shelving system installation. Increasing the amount of rails in a high density system adds another point load in the system lowering the point loads on all rails. Decreasing the height of the shelving is another option available to customers. This option will reduce the media weight across the system and may allow for an install without reinforcing the floor. Other solutions include changing the direction of the rails, using structural tubing, changing the configuration of the system or the last case scenario, floor reinforcement.
Floor reinforcement is common in high rise facilities where tenants reinforce the floor with steel plates or beams. Certified structural engineers will provide detailed information on how floors will need reinforced for customers to make a final decision on how to install a high density shelving system in their facility.