Recent articles on the various high-rise proposals have led to a lot of speculation among people from all walks of life.

It seems like everyone is always discussing these recent proposals by developers.

Although most of the proposals are still speculative, some members of the public and environmentalists are dead set against them. Still, most arguments and conversations have centred on the lack of supporting infrastructure, the current high density of buildings and the (lack of?) demand for these buildings.

People have rightfully complained on the excessive building spree that might be happening in the future and the lack of planning within our system. The scope of this article is not to question or discuss any of these concerns but rather to focus on something that has hardly been mentioned and which is often taken for granted in Malta: the civil engineering aspect of such buildings.

As one might assume, high-rise buildings are complex structures and their design differs to that of a traditional block of flats in many ways. As was pointed out by Karl Micallef in this newspaper recently, in addition to the analysis of gravitational forces, the structural analysis of such buildings often involves complex analyses of seismic forces, wind forces and complex shrinkage compression stresses.

These must all be analysed in detail before the design of such buildings can be properly carried out. The shape of the building, its height, orientation and proximity to other high rise buildings must all be studied in detail before any complex arithmetical calculations can be carried out.

This design often involves the use of sophisticated structural engineering software packages, as well as the input of various specialists in the engineering field.

Through the collective input of professionals, one can ensure the best possible building is constructed

Internationally, it is common for separate firms to be involved in the design of these buildings. It is rare for the architectural firm that designed the building to be responsible for the preparation of the structural/civil design, as these involve different sets of skills that might not be available in both (types of) firms.

Although both teams must work in tandem and be involved in most decision making, each of the tasks is so complex that specialists are often involved. Therefore, through the collective input of various professionals, each specialised in their own field, one can ensure that the best possible building is constructed. This type of approach ensures a cost-effective structure and a structurally efficient one, one which will benefit both the client and the public.

In Malta, the separate provision of such services is not very common. The reason is due to the perit (architect) notion which, in a sense, groups all specialisations together. Developers, therefore, task an architect with a job rather than split the job into phases and assign specialists to each.

When designing a tall building in London, for example, a common approach is for an architect to design the building, a structural engineer to design the structure and a geo-technical engineerto design the foundations. This ensures a professional approach.

The construction systems required for such buildings also differ from those in traditional buildings, although this must be pretty obvious to all. Tall buildings often rely on the construction of reinforced concrete cores, which provide the required stiffness in such structures.

This stiffness is important to resist seismic (and wind) loads, which can be crucial in the event of an earthquake. An engineer that previously worked on a high-rise in Malta once told me that, originally, the contractor had expected to construct the central core using concrete blockwork.

He was eventually convinced that a reinforced concrete core was essential in order to resist both vertical and lateral loads, which blockwork is incapable of resisting adequately at such heights.

It is important when designing these buildings that flexibility is also emphasised, to ensure that such buildings can be used for alternate uses.

Also, the construction of such buildings must allow the contractor to use the more efficient methodologies available today. Perhaps, if various tall buildings are planned, according to a proposed master plan, contractors will be inclined to invest in more sophisticated equipment, which will lead to an overall improvement in the construction industry.

Although I strongly believe that a master plan needs to be prepared that will identify zones, height limitations, green areas, etc, prior to the construction of such buildings, it is quite obvious that the only way forward in Malta is up. Perhaps through such projects, we will start to improve our practices and systems in the industries that, as of now, unfortunately lag behind our European counterparts on many levels.

David Grima is an architect and chartered civil engineer specialised in structural engineering.