Commercial space tends to get more expensive over time and relocating to a bigger space is time consuming and costly. This is why many companies in Northern Ireland with warehouses, workshops, and distribution centers are choosing to install mezzanine floors rather than relocate. A mezzanine floor is an effective way to get more space by utilizing the roof space that would usually be deemed as unusable. However, planning is needed so that it is not just installed in a haphazard way.
When we do site visits, one of the first questions we ask is what the floor is intended to be used for. Mezzanine floors that are used for storage of pallets require different load ratings than those that will be used for an office, a picking and packing area, or assembly. There is a difference between decks that are designed for evenly distributed weight and those that have weight from people, furniture, and other objects. There is also the consideration of fire safety and exit routes. The most expensive type of mistake that can be made is to have the wrong intended purpose when designing these structures.
Building regulations are legally binding requirements and not optional extras. Any Mezzanine floor which encroaches over a certain threshold footprint, or one that will be regularly occupied by personnel, falls under the Building Regulations and requires Building Control approval prior to the installation of that floor. This requires structural calculations, fire compartmentation, means of escape, staircases, handrails, and if the floor is used for storage, then also ventilation and lighting. It is a common misconception that a mezzanine is “just racking with a floor on top” and therefore not subject to these regulations. This is incorrect, and compliance is considerably more disruptive after construction than incorporating it during design.
Attention to detail is required for the fire safety of the design. Mezzanines may create fully enclosable or partially enclosed void spaces beneath them, which may require fire rated boarding, sprinklers, or smoke detection depending on the activities that are undertaken or the materials that are stored within that space. If the floor is located above the goods-in or dispatch areas, then the floor is likely to be a high traffic area and the distances to a protected means of escape will be constraining. This is something that we consider in the design along with the racking or storage layout that typically will be beneath the floor.
Another area where corners are cut is structural loading. With steelwork, the calculation is only half done — the other half is the load-bearing capacity of the new columns’ existing floor slab or foundations. Documentation on what a slab can carry is not always available, especially in older industrial units, particularly those that have changed use multiple times over the decades. Nasty surprises once the steel starts going up can be avoided by conducting a proper site survey that includes trial pits or existing drawings, if available.
For businesses considering if a mezzanine makes sense, the calculation usually boils down to cost due to square meters gained versus cost and disruption of relocating or renting more units. A well-specified mezzanine is in most cases considerably cheaper than moving premises, and if installed correctly around your busiest periods, it can be installed with minimal disruption to ongoing operations.
Before committing to a layout for extra storage, office, or picking space above your existing warehouse or factory floor, it is worth scheduling a site visit. These details shape what is achievable long before drawings are finalized, as every building has different clearances, existing racking, and structural quirks.