SOLITAIR Solitaire comprises eighty residences designed by Zecc Architects. The apartments surround a courtyard with space for greenery and communal areas. The roof is equipped with 1,550 m² of ND Water Retention System for Green Roofs With a protective geotextile layer between the waterproofing membrane and the ND WSE lt Water Retention Elements. These elements can be connected to drains equipped with a ND AFC-100 Adjustable Flow Control. The ND SV-300 Protective Geotextile is used as a filter layer on top of the Water Retention Element. Additionally, the roof is finished with gravel and solar panels. Spoorblok consists of 242 residences designed by OPL Architects. One of the roofs is equipped by Nophadrain with a standard sedum roof with a drainage system. This is the only roof in this project that does not have water retention. The other three roofs of Spoorblok are designed for water retention. The two roofs of 1,100 m² each and the third roof of 725 m² are equipped with ND WSE-50lte Water Retention Elements. These are specially designed for use on roofs with extensive vegetation and a standard slope and are therefore suitable for temporary storage of excess rainwater to relieve the sewer system. Ter bescherming van de dakbedekking of de thermische isolatie moet het ND SV-300 Beschermvlies onder het waterretentie element worden geplaatst. The ND FV-300 Filter Geotextile is used as a filter layer.