Merck Serono – high comfort, low impactThe new Merck Serono buildings and the refurbishment of existing buildings should reflect the company approach for a good working environment and an environmentally-friendly design.The concept approachA high energy efficient building cannot only relay on using renewable energy sources, but due to their limited energy density has to minimize the loads and optimize systems before hand.To minimizing loads the design team developed for the Merck Serono headquarter a facade system to optimize daylight supply on one hand, but control solar gains as a protection for overheating. The design came up with a high transparent double glazing, using low iron glass and the most neutral low-e coating combined with an Argon filling to feed as much daylight as possible into the building and ensure a good insulation value. An external, wind resistant, retractable shading device, made of small L-shaped stainless steal bars, was chosen as a reliable solar protection, which even at closed position allows a good visual connection to the outside. By the tilt of the facade, the system looks even from outside at pedestrian level quite transparent, but cuts down the solar gains to 15% or less, depending on the sun position. Daylight dependant control of the artificial lighting system reduces the electricity consumption but as well cuts down internal gains, due to the higher illumination efficiency of daylight. Glazed atriums as buffer spaces in between the buildings reduces thermal losses or use them to temper this spaces. In summer the large glass roof can be opened to ventilate surplus solar gains and keep outside conditions. A large water wall system works aside of a background noise source as a large humidification device in winter and allows for evaporative cooling in summer.