SealteQ started by dust-free milling of the exposed concrete surface. Subsequently, the surface was cleaned with a pressure of 500 bar. Cleaning the surface is important for repairing the concrete damage. Subsequently, the damage was tapped off, chiselled out and repaired by our specialists using a repair mortar. The steel expansion profiles were also dismantled and replaced. After this, a multi-layer cement-bound levelling system was applied to the Y-slope. Finally, a fully reinforced Triflex Pro – Park system was applied to the slipway. Challenging work because the application of both the levelling layers and the Triflex Pro – Park system was highly weather-dependent. Thanks in part to SealteQ’s work, the NDSM slipway has been renovated and has retained its status as a cultural heritage site.