The science of roofing - comment by the Klober Europe development team

A roof is a building’s last line of defence against the elements. But how efficiently it performs is a science in itself. The Klober Product Development team provides an insight into the depth of their work


Look up at a roof and what you see depends upon your perspective. If you’re in the construction business, your eye will naturally be drawn to the more technical aspects – why has a tile been chosen, how and where is the roof ventilated, what type of flashings have been used?? Professional interest goes beyond curiosity, as it’s the choices a roofer makes day in day out that secure his reputation.

One man who knows only too well the importance of roofing performance is Dirk Willen, who has been part of the Klober Product Development team in Germany for more than 20 years. Dirk takes up the story of the innovation, precision, testing and development behind each and every one of Klober’s products.

“Product development today can be so much more accurate and efficient than when I started back in the 1990’s. Then of course it was all still very much about using the drawing board and very basic digital facilities so it took some time to bring a project to fruition. Now, with CAD and 3D printing we can prototype much faster and make the development cycle a lot shorter.”

Whatever the drivers behind  product’s design, Klober has a highly experienced team that considers all of the many requirements it will need to fulfil. Weathertightness is the primary consideration of course and Klober has at its disposal the dedicated Technical Testing Centre of parent company Braas Monier. This has weather stations across the world, and from the data they collect it can feed in the most accurate climate intelligence to the profile of any new product. Wind speed, rainfall, UV exposure and temperature are critical factors as a roof in the southernmost part of France has very different demands placed on it to one in most of the UK. In Alpine regions you will find low pitch roofs with huge spans which need to be protected from the weight of heavy snow. Dirk added, “Durability and accelerated weathering tests are carried out to ensure products will withstand the severest conditions and as one of the few manufacturers in Europe to have our own wind tunnel we can subject them to exhaustive testing in line with the latest legislation and norms. We then examine whether we have existing tools available for production or will need to manufacture new ones. Of course, products such as vents and dry fixing accessories are a very visible part of any building means so we also need to take appearance as well as performance into account. A contractor wants to use products that are easy to use and offer the best long-term performance, but these days a tile or slate vent must be unobtrusive too. This makes colour as important as the vent profile so we ensure that pigments used offer the greatest durability. A colour will often look quite different once installed and also depends on the material used to manufacture it. Colour matching is a real challenge as the shade will vary between grooves, recesses and raised areas – it’s all very subjective. To obtain the best consistency we use a light chamber with precisely defined wave lengths and then cross-reference against the human eye. It’s always a battle against the elements which, over time, will always take their toll.”

Before manufacturing of a new product begins, it is also subjected to an extensive programme of trials and testing. These are carried out to ensure compliance with international and local standards as well as with Klober’s own, more demanding specification. Each individual test programme is based on a ‘failure mode’ analysis and it is only when all the processes are complete that the product is considered fit for launch. At this stage, the expert knowledge and insight of contractors is invariably drawn on prior to the commitment to full production. Dirk added “We regard our customers as partners and it is up to us to ensure we make their lives as easy as possible. We very much depend on interaction with them to further our deep well of knowledge and expertise in roofing built up over more than 50 years.”

Klober is well-known and respected for the way that existing products and their performance are considered integral to any research. This ensures that established product ranges continue to be fully supported, kept up-to-date and benefit from improvements ahead of the market. Dirk concluded, “In terms of answering technical enquiries this invariably means Klober is able not only to offer a solution which others may struggle to provide but have the confidence to address problems arising from complex roofing designs”.