Platform for growth
February 1st 2004

The benefits of mezzanine floors in the warehouse have long been realised, but there is growing demand for more complex structures across a whole range of applications. Charlotte Stonestreet visited The Mezzanine Floor Company to find out more Picture the scenario: increased demand means that your company is rapidly outgrowing its current premises. You are already making the most economic possible use of the space you have but you still need more. You consider temporary building solutions, but do not have the ground space required and want something more permanent. And a move to larger premises would mean severe disruption, not to mention the huge costs involved. So what do you do? Well, you have a mezzanine floor installed. One company specialising in this area (as you would expect from its name!), is The Mezzanine Floor Company. Founded in 1980 by joint managing directors John Porter and Keith Loveday, each structure designed, manufactured and installed by the company is a one-off, individually tailored for each particular site. Whether you want to maximise the amount of goods you can store, enlarge office space in an existing facility, or gain extra shopfloor space in your retail outlet, a mezzanine can provide a flexible solution that is relatively quick to install. Primary design feature Mezzanines are also in demand for new build projects. Rather than adding them at a later date, many large production and storage facilities now have mezzanines as a primary design feature right from the outset. Often in these cases, as well as helping to maximise space, the mezzanine will be essential to the very core operation of the facility. Due to the way logistics operations now work, large new distribution centres rely on automated systems from goods-in, through storage and picking, right to goods-out, says Alan Mooge, the Mezzanine Floor Companys marketing director. To facilitate the movement of goods through the building, operations need to take place on a number of different levels and that is where we come in. Essentially, in this type of application, the mezzanine forms a structure to support automated handling equipment and as such is a vital part of the overall operation of the facility. As Mooge says, It would be impossible for many distribution centres to run without a mezzanine structure. Production facilities Another growth area for The Mezzanine Floor Company is the use of mezzanines in large production facilities. In common with the major distribution centre projects, in this type of application, the mezzanine is often essential to the running of the operation. According to Mooge, a typical case of this type would be in food production where large vats of bulk ingredients are held at height and gravity-fed or pumped into mixing tanks below. The mezzanines are used to hold the bulk product in the air. This type of installation is also common in the chemical industry. Of course, with each mezzanine being individually designed, applications are by no means restricted to conventional storage, distribution or production facilities. An example of this is The Mezzanine Floor Companys largest ever project to design, supply and install multi-level work platforms to be used in the manufacture of wings for the new super-jumbo Airbus A380. Covering 7500m2, the three platforms are each designed to carry two wings while they are fitted out. These are very special mezzanines because, as well as being multi-level, certain areas have moving platforms, says Mooge. We also had to install them to a very tight timescale the wings were being constructed in a building next door and once they were completed they had nowhere else to go apart from our workstations! Like all the mezzanine platforms provided by the company, the workstations at Airbus are free-standing steel structures. Apart from the floor slab that they are built on, the mezzanines are not fixed to the building in which they are constructed. Every building is designed to very specific criteria what it will be used for, the actual structure, winds speeds it will be able to withstand, and so on, says Mooge. If you were to fix a mezzanine on to, for example, the building stanchions, the loads on the mezzanine would be partly passed on to the building structure itself, something that is has not been designed to support. Therefore, our structures are independent of the building. There is an alternative to the free-standing type of platform provided by The Mezzanine Floor Company in the form of a concrete mezzanine. The preferred choice in many retail department stores, concrete mezzanines are only really practicable in new buildings as the equipment required for construction would be too disruptive for a retrofit. Concrete also has to be given time to cure, a luxury that is not always available when tight deadlines have to be met. Also, once a concrete mezzanine has been installed it is very difficult to make any alterations. With the free-standing steel structures it is relatively simple to extend the platform or even dismantle it and move it to another position. Before the company starts to design each mezzanine it needs to ascertain what it will be used for and the loads it will be required to bear. Each floor is designed to accommodate specific loads. This will be a general load, which is uniformly distributed and point loads, says Mooge. Point loads come from items such as shelving, where there will be increased loads coming down the frames, at specific points on to the mezzanine deck. If there is any large piece of equipment going on to a mezzanine, it will inevitably stand on small feet, also resulting in imposed point loads. Rather than design the whole mezzanine to accommodate the heaviest load, specific areas within structure are constructed to handle heavier point loads. Areas can also be specifically designed to house machinery with high levels of vibration. Column grid Another important part of mezzanine design is the column grid, which gives the space between the supporting columns along the width and length of the platform. According to Mooge, there is tendency for customers to want as few support columns as possible, leaving the area underneath the mezzanine relatively free of obstruction. However, generally speaking, the longer the distance between columns (ie. the fewer columns there are), the more expensive the mezzanine. This is because the steel sections, both columns and beams, will increase in size. In fact, the company has designed platforms with spans of 15m plus, but this does work out to be comparatively expensive and most use a much smaller column grid. However, large spans may be necessary to build over obstacles at ground floor level. At this stage it is very important to consider not only what will be happening actually on the mezzanine, but also what the area underneath will be used for. This can have a substantial effect on the overall design. For example, the use of sizable mobile equipment on the ground floor can be restricted by a smaller column grid, or there may be a large piece of static machinery where a column needs to go. In such cases the mezzanine can be designed around these obstacles by placing extra columns either side of static machinery or having a corridor of wider beams to provide required access. The height of equipment to be used under a mezzanine should also be noted and allowed for in the design. In the case of large new build distribution centres, this information will generally be provided by the customer in a series of detailed drawings of the complete project, showing precisely where each piece of equipment will be and every process will be carried out. The Mezzanine Floor companys platforms normally have the main hot-rolled steel beams connecting all the columns in one direction and secondary cold-rolled steel joists connecting in the the opposite direction, fitting into the web of the main beams. However, some applications may necessitate hot rolled beams in both directions, together with cold rolled joists in between. The most common decking material is 38mm particle board, which is used on around 70 to 80% of the companys installations. For facilities where there is a possibility of spills, or wash down is required, galvanised steel grating may be used. Steel plate can also be used as decking material, says Mooge. From time to time we use particleboard with steel plate on top to ease the wear and tear caused by very heavy loads moving around on the mezzanine, for instance electric powered pallet trucks. We have also covered particleboard with a vinyl layer with welded seams for use in the food industry. A very important factor to remember when considering a mezzanine is that all mezzanines need official Building Regulations approval from the local authority. A major part of this is meeting fire regulations particularly in regard to incorporating appropriate means of escape. Each design must be such that in the event of a fire, fire officers can get into the building and safely put out a blaze before the structure collapses. Any reputable mezzanine provider will make sure that this is the case and be able to advise on specific rules pertaining to certain applications. Approved design Once a customer has approved a design, The Mezzanine Floor Company will submit the drawing, along with structural calculations of every component, to the relevant local authority to gain approval on behalf of the customer. When this has been gained which Mooge says normally takes between five and eight weeks the company delivers to site and completes the installation. To find out more about The Mezzanine Floor Company and the varied applications it has fulfiled, visit www.mezzanine.co.uk. The company will also be exhibiting at IMHX, Hall 17 Stand U48.

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