Steeling a march 
on concrete

Mladen Petrov

Modern structures cannot exist without steel – and warehousing is no exception. But concrete – which still rules the roost in warehouse construction – can be replaced by steel, with its variety of advantages, including greater fire safety

It is a material which can be used for almost any purpose and can be recycled; even a warehouse assembled from it can be dismantled and turned into motorcars. It is environmentally-friendly and when everything has to be completed “yesterday”, it speeds up the construction process. We are, of course, talking about steel. The warehouse industry has two clearly distinct philosophies – the pro-concrete and the pro-steel, with the first still taking pride of place. Marta Dziarnowska, Central Europe director of Arcelor Mittal, comes down firmly on the side of steel: “Unit cost is not the most important thing. You have to remember that the speedier construction times when steel is used can prove to be less expensive in the long run. This can be seen in office-building construction, where completing a project six months earlier than planned means the building starts generating revenue much sooner, in the form of rents.”

Modernity versus tradition

A cross-section of a steel pillar is smaller than that for concrete elements, which is especially important in warehouse buildings since they leave greater space for storage. The lighter weight of a steel structure means the foundations of the buildings also weighs less. However, as Robert Teperek, Arcelor Mittal director for expansion in Poland, argues: “I must admit that in our region the list of investors willing to use steel isn’t very long. The decisive thing here is that apart from costs, there is an ignorance of the material’s features as well as its tradition. They want concrete and that’s that.”

Hence steel producers are continuing to look for increasingly effective ways to convince investors about using steel. Should they not decide to use steel on a wider scale, they can be persuaded to use it for new solutions. It is no secret that fire-prevention regulations are bothersome for the developers of logistics facilities, primarily due to the large number of safeguards that are required.

Greater security

Developers have two fire-prevention systems to choose from: passive and active. The first include fire-proof walls and doors as well as the sealing of technical passageways and the systems securing fire-prevention structures. An active system, on the other hand, detects a fire and includes smoke removal systems, water hydrants and sprinkler units, lighting of evacuation passages, warning systems etc. There is no clear cut answer to the question of which system is superior. Rafał Mirowski, a technical manager at warehouse developer Segro, heaving a hopeful sigh, believes that: “Comprehensive protection must be a combination of both the above mentioned types of fire prevention. We fit office buildings with standard complex BMS systems which control a building’s systems in a pre-set manner, automatically alerting the nearest fire brigade, opening passages and indicating evacuation routes. Perhaps such a standard will soon no longer be something unusual in warehousing parks.”

As simple as IKEA kiks

There are no shortages of advanced solutions on the market. A new fire-prevention solution by Arcelor Mittal will soon appear, devised primarily with warehouses in mind. The industry claims that it is just as easy as assembling IKEA furniture. It involves installing a symmetrical partition of 2.5 x 1.25 metres built of several layers of glass wool, plaster and silicon between two steel Al-Zn plated sheets. All the layers are glued together with special adhesives. This unit is used to divide warehouse space into several smaller segments so as to minimize the possibility of fire getting from one part of a building to another. Tests carried out by the producer have proven that while a fire-induced temperature in a warehouse amounted to 1,200ºC, it was 12 times lower on the other side of the partition wall. This solution is also effective for fires up to 15 metres in height.

Rafał Mirowski of Segro is of the opinion that: “This may be an interesting solution but it is good for only a limited number of customers. When building warehouse space we have a typical tenant in mind that does not require fire-prevention partitions to such an extent. Usually systems which ensure up to 2 hours’ fire resistance or even that prevent the spread of fires – are sufficient.”

Multiple-use wall

The advantage of being as easy to assemble as an IKEA product is the result of being able to avoid the use of heavy construction machinery and, additionally, of reusing it in another warehouse, dismantling it and setting it up in a new location. An investor can rely, first and foremost,on the security – in the case we have been describing the fire-resistant period is four hours fire, twice as long as in a regular warehouse. In France, for example, the first country where this solution is available, such fire resistance is required in warehouse buildings by a growing number of insurance companies.  In addition, the partition wall provides high acoustic insulation, which can be used in production facilities.

Arcelor Mittal intends to open factories outside France due to the low cost of such an investment and the short time required to set up a production line. The manufacturer is taking a close look at the CEE region, where it is already applying for patents. ν