Q: What roofing trends are we seeing at the moment?
A: Wood, or timber, is still used for structure in most residential applications, although steel-frame sections are growing in demand, mainly as a result of poor timber quality and shortages. There is a move towards lightweight roofing materials such as steel and composite tiles. This is largely due to the cost of heavy roof materials, such as concrete tiles, which have been used traditionally. Transportation is also a factor in terms of cost and environmental considerations, so lighter loads have become more popular. Another trend is that of a roof material’s suitability for solar applications, which help address SA’s energy challenges. New builds, in particular, plan for current or future solar installations, so the choice of roofing materials has to be compatible. It’s encouraging to see SA picking up on the European demand for sustainable, recyclable roofing materials, which have a lower impact on resources and the environment.
Q: What sustainability practices in the production of roofing materials are being applied?
A: It is difficult to confirm the differing practices individual manufacturers adhere to but given that most traditional roofing materials have seen little change, it will be dependent on the source material manufacturer (such as cement or steel) to implement sustainability practices. To a large extent, sustainability is associated with using fewer raw materials and increasing a product’s longevity. Innovation such as the Harvey EcoTile is conceived with sustainability in mind and is therefore recyclable, uses a high percentage of waste material, and is produced through a water-free manufacturing process. This type of revolutionary roofing system will contribute to a building’s green credentials in future.
Q: How popular is solar roofing today, and do you see this becoming a standard in the near future?
A: The industry is experiencing unprecedented interest in solar systems. Although the high cost of solar-rooftop systems constrains growth, the market is forecast to grow by more than 9.5% per annum over the next five years. Owing to the electricity crisis, declining cost of solar PV modules and our country’s abundant sunlight, we can expect to see a rapid increase in solar-rooftop applications, not only in commercial and industrial, but also residential buildings.
One of the concerns about the installation of solar systems on older roofs is that they may compromise the roof and create leaks. This can be prevented by contracting experienced installers and utilising purpose-designed materials. Certain roofing options such as concrete/clay tiles essentially haven’t changed in decades, so one can expect that modern products will be more suitable as they are purpose-designed to accommodate solar installations.
Q: Similarly, how green-friendly are roofing materials today in terms of water harvesting?
A: Rainwater can be harvested from most roof types. But it is important to know if the material or the paint used on the roof or in gutters could contaminate rainwater. Generally, water harvesting is not suitable for roofs with lead flashings, covered with lead-based paints, bitumen and tar, or treated timbers. All these elements can contaminate the water supply. Run-off water from roofs freshly coated with acrylic-based paint, new concrete-tiled roofs, and new metal roofs should ideally be discarded as it is not drinkable for the first few run-offs. However, Harvey EcoTile was designed with water harvesting in mind and is therefore perfectly safe.
Q: How varied are the roofing options between commercial, residential, industrial sectors?
A: There are many varied roofing options available, including steel – corrugated and inverted box rib (IBR), concrete tiles, clay tiles, and slate and thatch, to a lesser degree. New products such as mineral-composite roof tiles manufactured from waste material are being introduced as sustainable, green alternatives. The material used depends on the actual design of the roof but, generally, commercial and industrial roofs tend to favour steel, whereas the majority of residential roofs comprise concrete or clay tiles and corrugated iron. In rural areas, IBR corrugated types of roof cover are popular for residential homes but the aesthetic appeal of tiled roofs are seen as aspirational. Harvey thatch tile, as an alternative to natural grass, has grown considerably over the past couple of years.
Q: Are the installation practices green-focused?
A: Installation processes are typically tried-and-tested methods and, therefore, not particularly green-focused … yet. Installations are dictated by the materials used – for example, steel structures in large-scale commercial designs or timber trusses for residential concrete-tile roofs. The difference is evident when a lightweight roof material is used to reduce the need for an over-designed roof structure and resultant foundation requirements. A lighter roof tile requires much less timber, so the impact on the environment is obvious. However, it also means that less transportation is required resulting in lighter loads, fuel savings and reduced carbon emissions.