Greenhouse Collection at the Singel, whose 1978 basic structure has been maintained, is a sustainable building on multiple levels. After completion it will acquire BREEAM ‘Excellent’ certification. To attain this level, the utmost attention has been given to CO2 reduction (solar panels, heat pumps, nearby public transport, …), energy saving (Energy efficient elevators and lighting), water saving (leak detection, usage monitoring, low use appliances) and health & wellbeing (Lighting design, controlled air quality, acoustically optimized spaces plus a range of facilities).