Extreme temperatures - how will flat roofing evolve with climate change?

According to some industry estimates, residential and commercial buildings are responsible for between 30-40% of carbon emissions, levels that could be significantly reduced depending on the type of roof chosen by the building owner, particularly when combined with other factors such as the correct levels of insulation, writes Justin Pitman, sales director for Proteus Waterproofing.

It is all part of the many and enormous challenges facing the roofing industry, which is under increasing pressure to minimise its environmental impact and offer sustainable alternatives. These are challenges, some of which the industry has already embraced – good examples being the growing number of green roofs, proven to significantly reduce energy use and blue roofs, which are helping to offset the problems of flash flooding.

Flat roofs in particular that are constantly exposed to the elements, are under attack as never before from increased levels of UV light leading to increased algae growth and extreme temperature variations both hot and cold, which means that traditional waterproofing products have to perform even harder to maintain integrity.

In the next 50 years, based on current UK climate change projections, it is suggested that we shall experience warmer and wetter winters, hotter and drier summers and will almost certainly have to face a higher frequency of extreme weather events.

The highest temperature recorded in the UK was in 2022 with a record of 40.3 degree Centigrade. At the other end of the scale, Braemar in Scotland reported a new low of minus 27.2 degrees centigrade in 2016. Such temperature fluctuations contribute to the intensity and frequency of thermal shock as it is better known, which can significantly affect the long-term performance of a flat roof.

Thermal shock is the damage that can occur when the roofing material on a building expands and contracts in a short space of time in response to temperatures rising or falling too fast. There is nothing new about this process. Manufacturers such as Proteus have always been aware of this phenomenon and have developed products and systems to cope with this and the worst of Britain’s weather.

It is what the weather future holds that presents the greatest challenge. According to Justin Pitman suppliers and manufacturers will have to take into account extreme weather events and temperature fluctuations by developing more durable products and systems.

Bitumen based built up felt systems are particularly vulnerable to major temperature changes, but Proteus already has products designed to work with the kind of heat experienced in middle eastern countries, with the equal ability to perform well at low temperatures.

Future extremes in temperatures are also likely to affect the opportunities available to install a new roof. Most roofing experts consider that the best temperature range for roof installations is between 21-27 degrees Centigrade, but it is also too cold when temperatures drop below 4° C. That said Proteus have still remained ahead of the curve with liquid systems that can still be installed at such low temperatures, dependent on the right conditions.

So how will the roofing market change in response to climate change? As already mentioned, we are seeing an increased demand for green roofs with their enhanced insulation properties and blue roofs to help control excess rainfall.

We are also seeing pressure to develop roofing systems that are not only energy-efficient, but energy-producing such as the growth of solar panels or alternative wind energy.

Climate change is here to stay, and all industries, including roofing, need to make plans to adapt. The most successful roofing companies will be those that work with both clients and regulatory agencies to design and install roofs that offer the greatest longevity and performance even under extreme conditions.

Change is here – extreme change at that – and we should all be prepared.