This is why Protan has developed a blue roof system that reduces the risk of flood damage.
Protain BlueProof is sustainable, environmentally friendly and durable. It is designed to manage extreme amounts of precipitation.
This kind of precipitation is becoming increasingly more common in our cities with torrential rain leading to flooding in the streets. Existing stormwater drain and sewer systems are not built for such extreme rainfall. As a consequence, millions of pounds are lost in damage every year.
The need to establish a surface water system to tackle such extreme weather events is clear. But the space available for this is limited in densely populated areas. In addition, it is expensive to dig up streets and pavements. The solution lies overhead: Protan BlueProof transforms the roof into a surface water reservoir that slowly drains extreme rainfall into the sewer system.
Effective water drainage and safe surface water management are key concepts in describing the technology behind Protan BlueProof.
On most roofs the water drains away as rapidly as possible. Protan BlueProof enables a slower tempo so that the water is sent gradually, and in a controlled way, down to the sewer system. We call this water attenuation.
This means that not all precipitation is sent back to the ground at the same time, but that some of it stays on the roof. In this way the congestion that leads to flooding and consequent damage is avoided.
Most roofs are built to bear heavy weights, which is why it is usually no problem to attenuate the water runoff.
Imagine you have an ordinary surface of 1 000 M2 m2 and there is a downpour of 50 mm in one hour. This means the roof will strain the sewer system with 50 cubic metres of water in an hour.
But if we keep the water back, it will accumulate on the roof to an equivalent 50 kg per square metres.
In the north of Norway for example, flat roofs have a defined weight bearing capacity and, in most cases, can hold more than 300 mm of rainfall per square metre. This is equivalent to 300 kg.
With Protan BlueProof, the drainage slows down and it will take up to 24 hours for the total 50 cubic metres of water to reach the sewer system.
Protan always offers the necessary training for installing BlueProof and we are on site with our inhouse technicians from the first project.
Before the roof system is installed, the roofing contractor and its roofers must have undergone a training programme known as Roofing School 1. For BlueProof installation, there is an additional module about the installing and function of this advanced system.
In order for the BlueProof system to gain approval from SINTEF, requirements have been set for the qualification of the roofing contractors’ project manager. There are no specific requirements for individual training, but Protan offers support throughout to ensure competence.
At the end of the project, Protan undertake a function/integrity test together with the roofers.
Extreme rainfall leading to major flood damage is a part of our future weather picture. Researchers at the Norwegian Meteorological Institute are in no doubt that we must prepare ourselves for extreme precipitation. Their calculations show an expected 18% increase in precipitation by 2100, if the emission of greenhouse gases continues as it is today.
All the indications are that we can expect more intense precipitation with greater and more frequent flooding. Northern and Eastern Norway are expected to see the most extreme weather.
In densely populated areas the surface water is mostly discharged into drainage pipes and separate surface water pipes. But the drainage network is not designed to cope with the amount of rainfall we are seeing now.
By choosing the Protan BlueProof roofing system, you get a blue roof equipped to manage the weather of today and the future.
Protan products have among the lowest carbon footprints in the category of roofing materials. Here you can browse our products by category or application area.
