We take a closer look at temperature control in the modern construction industry.
The pyramids of ancient Egypt remain one of the great feats of construction and engineering. But for any construction professional who has ever worked in a climate similar to Egypt’s, one wonders: how on earth did they do it without air-conditioning?
The modern Dubai skyline is dominated by structures that vie for prominence and attention. From the Burj Al Arab to the Burj Dubai, these seem to have been built for much the same purpose as the pyramids of Egypt: to inspire and awe. However, modern construction relies on very different tools and techniques.
Temperature control in the construction industry has progressed steadily, focusing on advances in water chillers and air-conditioning. One application utilised regularly on-site is the use of chilled water coolers for concrete batching.
In 2002, a study conducted at the Centre for Transportation Research at the University of Texas in the US concluded that concrete produced in a hot climate without ice or chilled water added will be subjected to greater stress, and will result in reduced long-term concrete performance.
COOLED CONCRETE
In order to reduce such stress on concrete, experts recommend the use of cooled concrete, which can be produced through the mixing of chilled water or ice in the concrete mix. This technique is common on construction sites in the Middle East region, where maximum temperatures exceed 45°C during the summer months.
In addition to applications for concrete cooling, ‘comfort’ cooling, which is the use of temporary air-conditioners to lower ambient temperatures for workers, is becoming the norm for many construction projects during the summer. Many project managers find that the cost of installing temporary air-con on-site is more than covered by the increased productivity of workers, especially when temperatures rise above 30°C.
UTILITY INFRASTRUCTURE
A frustrating dilemma is how to get around the fact that most construction occurs in areas with growing populations that put pressure on utility infrastructure. This means large construction projects almost inevitably occur in regions where the local utility company is already stretched to the limit, resulting in long delays when it comes time to connecting the completed buildings to the utility grid.
The delays are caused due to the fact that, in a hot climate, a non air-conditioned building cannot be grouted or painted, as the high temperatures will cause the materials to dry too quickly and crack. By using temperature-control equipment, developers can fast-track the fit-out stage of a project through dehumidifiers and air-con to create a cool, dry atmosphere.
Another fast-track solution that can be provided by temperature control is the cooling of switch (utility) rooms. Rather than waiting for a utility hook-up in order to complete commissioning, a contractor can use a temporary temperature control system to reduce the temperature in the switch room to a level where it can be commissioned, thus enabling the hand-over of the property.
Once a building is completed, the need for temperature control does not necessarily fall away. In some climates such as the Middle East, high temperatures mean that, in order for tenants to move into a newly-constructed building, it will have to be connected to a district cooling system.
District cooling is a rapidly-growing industry in which providers build central plants that distribute chilled water to an urbanised or industrial area. By utilising district cooling, building developers are able to provide cooling to an entire community in a far more efficient manner due to economies of scale. The global trend of deregulation of power, combined with many governments choosing to outsource various utilities, has increased the interest in district cooling.
However, district cooling plants are a long-term investment, and take between three and five years to complete. This means that many developers find themselves in a situation where buildings are ready for occupancy, with distribution systems already in place for chilled water, but without a plant to provide this chilled water.
By contracting a specialist temperature-control rental company to provide temporary chilling packages, developers are able to hand over their properties months, and sometimes even years, ahead of schedule, resulting in substantial cost savings.
TECHNOLOGY ADVANCES
Scholars disagree as to the length of time it took to build the pyramids, yet even a conservative estimate suggests that a single structure would have required decades to construct. Our modern-day equivalents take only a matter of a few years. The reason for this is the advances that have been made in every aspect of technology, which allow developers to plan, engineer and build projects at a rate never before seen in history.
Although just one tool among many available, temperature control is nonetheless a necessary element throughout the lifecycle of a project. From chilled water for concrete mixing to comfort cooling for worker accommodation, to cooling of entire building developments, the applications of temperature control are varied and important, serving to lower costs and to fast-track the building of massive projects.