Status: 08/14/2023 06:00 a.m
As a result of climate change, trades are also changing, for example that of roofer. The demand for solar systems and green roofs is increasing. Carports are also greened. This effectively expands the unsealed area in cities.
Martin Granseuer pours a substrate for so-called sedum plants onto the roof of a carport in the north of Hamburg. It actually has nothing to do with plants. He is a master roofer and an expert for roof reports. However, green roofs have recently also become his area of responsibility, and for smaller roofs of up to around 600 square meters, his company does the planting itself. Gardening and landscape companies are only involved for larger roof areas.
Plants that are particularly heat-tolerant are placed on the roof
Sedum plants are heat-tolerant, thick-leafed plants. In the last step, on the fifth day of work at this carport, you come onto the roof. Before that, Granseuer explains, the carport roof was rebuilt: “With this carport, the seal was leaking and the entire substructure was dilapidated. We dismantled everything down to the steel substructure and then practically a new one Roof truss created, a new wooden formwork and then very important: applied a root-resistant seal, created all edge connections with metal sheets and then put the greenery on top.” A good year will pass before the sedum plants, which are otherwise common in rock gardens, bloom. Just like other gardens, the mini-garden on the carport also has to be tended to and serviced on a regular basis. For example, there are pebbles on the edges next to the substrate surface, which must remain free so that the green roof can continue to fulfill its function.
VIDEO: Green roofs: tips for location, construction, plants (15 min)
Green roof protects carport from heat damage
A green roof is not just a chic garden extension, says Granseuer. It also has important tasks with a view to warmer temperatures and extreme weather events because it protects the roof waterproofing: “Then it is no longer exposed to these very high temperature fluctuations. In summer we like to have 80 degrees Celsius on the roof. In winter 20 degrees Celsius , that’s toned down a bit at the peaks. The water doesn’t go straight into the sewers, it’s actually being held back on the roof.”
Water storage function is particularly interesting in cities
A layer of granules is the basis for the green roof.
Because the green roofs absorb rainwater and thus protect sewer lines from overloading, for example in heavy rain, the city of Hamburg has been promoting green roofs by private individuals with up to 40 percent of the construction costs for several years. Such a green roof costs around 230 euros per square meter, and it is cheaper for larger areas.
Climate change is changing the profession
In addition to green roofs, Granseuer and his colleagues are increasingly building photovoltaic systems on roofs. According to Ulrich Marx from the Central Association of the German Roofing Trade, both areas together now account for a good fifth of the total turnover of roofing companies. There are around 15,000 companies in Germany. And their tasks are becoming more diverse, says Marx: “There was a first wave of photovoltaics about ten years ago, when companies noticed increased demand. This was also due to the fact that the production of photovoltaic modules was being pushed very hard in Germany is.” He has observed another very significant increase in demand since last year: “Since the outbreak of the Ukraine war and the energy crisis that followed, the desire for alternative energy sources has become particularly strong.”
Further information
Many carport or shed roofs are suitable for greening. The plants should be robust and easy to care for. more
Climate change: roofing trade attracts young people
According to Ulrich Marx, the fact that roofers are actively involved in climate change attracts young people. There has been a constant increase in trainees for years. Richard Ockert recently finished his training. He became aware of the company in Norderstedt at an information event organized by the Chamber of Crafts: “I definitely wanted to go into the craft sector. It’s great in summer, less so in winter, but what can you do. Install windows in the pitched roof area, Garages, working with sheet metal, that’s a lot of fun for me.”
According to the central association of roofers, 9,000 new trainee contracts were concluded nationwide last year. Three new apprentices will also start at Martin Granseuer in the autumn, he has a total of 23 employees. The inquiries and orders would be enough for twice the team. Because he is so busy, it took a year before the Hamburg carport could finally be worked on. His prognosis: The areas of maintenance, repair and service life extension of roofs will continue to increase: “We will do our part and will not postpone work. It is a very future-proof job.”
Further information
They look great and are very useful: green roofs. They are suitable for garages, pitched roofs and even roof terraces. more
In recent years, agriculture and forestry in particular have seen a veritable boom in training. more
The global climate crisis is also affecting northern Germany. How can the energy transition succeed? Which are the best solutions? more
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NDR Info | 08/14/2023 | 7:41 a.m