With its historic masonry structure, the Hanover State Opera House has been one of the most iconic buildings in the capital of Lower Saxony since its construction in 1852. Over the years, the historic copper roof had fallen into disrepair and developed leaks at the seams and joints. To prevent water damage in the rooms below, the defective connections and transitions were sealed using the Triflex ProDetail detail waterproofing system with geotextile reinforcement. The waterproofing specialists from Grossmann & Stühmeier GmbH were thus able to complete the renovation work in a very short time, despite unpredictable weather conditions.