In this age of increasing concern for the health of the planet it is more important than ever to look at ways of minimizing the long term impact of buildings upon the environment and to investigate new methods of sustainable construction.
A new kind of building technology is emerging as an environmentally friendly alternative to conventional building methods. This technology produces structures which are highly efficient in terms of the amount of material used in their construction, require no permanent foundations, can be relocated easily, and can recycled.
The buildings in question are in fact a new generation of inflatable buildings. These are no ordinary inflatables however. They are designed using the latest CAD technology and structural analysis software and are constructed from modern, fire retardant, composite textiles which are cut and joined using techniques developed form aerospace manufacturing. This enables the buildings to operate at higher pressures than conventional inflatable structures producing much stiffer, stronger structures.
It’s important at this point to make a distinction between air-supported buildings and inflatable buildings. A traditional air-supported building is one which is comprised of a single layer membrane attached to the ground around its perimeter. Air is blown under the membrane to lift it off the ground and form the shape of the building.
An inflatable building on the other hand, uses two layers of membrane connected together typically using spars made from the same material. The cavity formed between the layers is pressurized with air producing a rigid structural element which allows large span structures to be achieved.
The structures, pioneered in the UK, are extremely weight efficient and are highly portable yet they have the strength of metal-framed portable buildings and can be made into virtually any shape.
So what makes them so environmentally friendly? Well, firstly, the majority of a finished inflatable building is made from fresh air. Analysis of a finished structure shows that the amount of textile used represents only 0.5% of the volume of the structure. For example, one square metre of a 500mm thick inflatable wall has a volume of 0.5 cubic metres but the quantity of fabric used in its construction is only 0.0025 cubic metres. An inflatable building must surely be the most efficient of all building types in terms of the amount of raw materials used compared to the volume of the finished structure.
Since the textiles are supplied in roll form, the materials required for an entire building can be transported in a single medium-sized van thereby minimizing the effect of transporting raw materials upon the environment.
Thanks to new initiatives, the scrap material produced during the manufacture of inflatable buildings can be collected, recycled and made into new composite textiles.
The inflatable buildings produced have a long life expectancy but when they do eventually reach the end of their service they can also be recycled using such services.
Another environmental benefit of inflatable buildings is that they do not require permanent foundations. Conventional buildings usually require concrete foundations which are permanent and cannot be moved. An inflatable building would typically be anchored using spiral anchors which are literally screwed into the ground. If a building needs to be relocated, the anchors are unscrewed and used again. The flooring used in the buildings is modular and can be laid on top of the ground. It can also be re-used if the building is moved.
Once an inflatable building has been moved, there is no lasting impact upon the site where it used to be.
Another important consideration when assessing the environmental impact of a building is the energy used throughout its life. Because the new generation of inflatable structures are of a welded construction (as opposed to stitched), they are virtually air tight. Conventional stitched inflatables require high power electric blowers which run constantly. The new structures require much smaller blowers which are connected to a control system which only activates them when the pressure in the structure falls below a certain level. The blowers then run for a few seconds to top up the pressure.
The low power requirement for these structures means that it is entirely possible to use solar power to provide the electricity required for their operation.
If the environmental impact of a new building is a major concern, then the benefits of using these new inflatable structures are well worth consideration.