Elevated floors make up some of the more technical and expensive components of industrial, commercial and residential building frames. They come in many forms and can make up the heaviest part of the building. As such it makes sense to focus attention on them and provide guidance on what types of floors are available in South Africa and the benefits of each type of floor.
Chapter 12 of our Red Book contains useful information on Metal Flooring types that are typically used in industrial applications. These include grating or open grid flooring, expanded metal flooring, profiled plank flooring and solid plate flooring – commonly known as Vastrap flooring when patterned.
Metal flooring is used extensively in the mining industry, in process and chemical plants, petro-chemicals refineries, cement and fertilizer plants, pulp and paper factories, power-stations and utilities such as sewerage works and water treatment plants. The flooring is generally required to support pedestrian and light vehicular traffic and can provide excellent elevated access in areas that are congested by equipment when used as platforms and walkways.
The advantages of the open types of flooring are that they represent an economical, lightweight system that permits the passage of light and air to areas below, they are virtually self-cleaning and do not allow dust or rubble to accumulate, and allow oil and water to drain off easily. Solid plate floors are commonly used where spillage has to be contained or where a high level of hygiene is required.
When it comes to commercial and residential buildings, as well as mezzanines in industrial buildings, steel is typically used as permanent shuttering with concrete making up the rest of the flooring. Various decking products and their technical specifications are provided at the back of the Red Book. The common thread in all these systems is the use of slightly more steel and less concrete as compared to conventional cast in place or precast systems. Not only are such floors lighter in weight but they also consume fewer materials and more importantly involve the use of less fresh water and hassle.
They do this in three ways. Concrete on steel permanent formwork reduces the overall weight of structures and there are savings in water usage simply because less material is used. Secondly, the use of slightly more steel and less concrete allows for savings because much of the water used in steel production need not be fresh drinking water. The use of steel both as formwork and permanent structure reduces waste and debris on site and this has serious implications on the use of fresh water for site cleaning and waste removal.
Finally, there are light steel floor systems that are typically used in residential and smaller office buildings. These systems are composed of lipped channels or trusses spaced at close proximity to support a flooring system. This flooring system can be made from steel pans, fibre cement board, Oriented Strand Board or a host of other flat sheets that can support floor loads between the channels and trusses. In many cases, the boards are built up to provide sound isolation and heat insulation, while a ceiling system below the channel or truss can also help in this regard.
Light steel floor systems are typically constructed as dry floors – without concrete or screed pour – and this makes them environmentally friendly. Not only are the sites unusually clean but there is little debris to take back from site. Moreover, disassembly possible re-use of building materials is also possible at the end of the life of the building.
The Red Book is an incredible repository of useful information on how elevated floors can be constructed using various methods that are easy to design, fabricate and install. These floor types are applicable to industrial, commercial and residential buildings. These floors are preferred because – as compared to competing systems – they are easy, clean and sustainable ways of constructing elevated floors.