Convertible shading roof for the Prophet’s Mosque in Medina
This project is directly linked to the expansion of the Holy Mosque of the Prophet in Medina. Together with the old mosque, the newly designed buildings form two inner courtyards that required efficient air conditioning. SL Rasch developed a convertible shading roof consisting of six large umbrellas per courtyard, each with a span of 24 metres. From the moment they begin to unfold, the umbrellas radiate a unique magic: all at once, the rigid wings lift silently into the air, spread out and shade the courtyard with a translucent, vaulted covering – a fascinating transformation that converts the outdoor space into a big, bright hall.
A particularly light and high-strength Teflon fabric that falls in soft folds was developed for the membrane. Besides being extremely UV-resistant and fireproof, its friction and wear properties are ideal for folding. The removable carbon fibre cladding that protects the folded membranes from wind, sand and dust is also new. In summer, in addition to providing shade, the umbrellas also emit cooled air from the base of the masts and the capitals, creating a sea of cold air that keeps the courtyard at a pleasant temperature all day long. In winter, when the nights in Medina are cool, the umbrellas open up in the evening and prevent the warmth of the day from escaping. The software-controlled umbrellas open and close automatically depending on the position of the sun, but are prevented from doing so when the wind reaches speeds of more than 50 kilometres per hour by an anemometer. Overall, in keeping with local weather conditions, the system is designed for a maximum wind load of up to 155 kilometres per hour.
The reinforcements and webbing of the membranes are accentuated by decorative light blue ribbons. This gives the umbrellas a more sculptural, three-dimensional look when seen against the light and makes them appear to merge with the architecture of the mosque. Like the arcades around the courtyards, the main masts are faced with marble and adorned with brass capitals. When folded, the umbrellas look like small, slender minarets. As a result, their light, timeless form complements the traditional architecture rather than competing with it. In 2014, the project was presented with the Abdullatif Al Fozan Award for Mosque Architecture.