oa Zero energy and emission building laboratory Qatar: Experimental study and calorimetric measurements on building envelopes under outdoor exposure

Intelligent building envelopes can significantly reduce the environmental impact of our buildings during their whole life cycle. Intelligent means that user comfort is reached through subtle use of devices to manage indoor climate (temperature, air quality, humidity and light) in the most energy-efficient way while involving outdoor conditions as suitable. A promising methodology consists in keeping the building services as basic and user-friendly as possible without compromizing energy efficiency and minimal environmental impact. This is achieved through active control of the building skin functions, adapting them to the constantly changing outdoor conditions. This approach not only fits to new buildings, but can be implemented as well on existing building stock, for example in the context of a renovation/refurbishment project. Qatar will see intensive building activities taking place in the coming years. A great challenge and opportunity to put the intellectual approach into practice. Since end of 2012, the ZERO ENERGY AND EMISSION BUILDING LABORATORY of Hydro Building Systems GmbH which has been set up at Qatalum can be used for experimental researches on façade systems under natural weathering conditions. The target of the first series of measurement is to analyse the energetic efficiency of four different types of façades. Reference is a SSG façade with insulating double glazing with a g-value of 0.16. Optionally, an external blind can be operated. Further façade types are a SSG façade identical to the reference façade, fitted with a fixed external brise-soleil made up of aluminium blades, a high insulation stick type façade with triple glazing and Venitian blind in the pane interspace as well as a box-type window with turn/tilt sash inside and parallel outward sash outside with a Venetian blind fitted in-between. Calorimetric measurements regarding the required energy needs show that a fixed brise-soleil (blades) reduces the cooling energy requirements by approx. 22%. An external venetian blind offers potential savings of approx. 40%. Replacing a standard stick type façade with double insulating glass by a high insulation façade with coated triple glazing and integrated sun protection, the cooling energy consumption can be reduced by more than 57%. A double skin box-type window solution with sun protection in the interspace cuts the energy consumption for cooling the room by 40%.