Seville, Spain - Seville is one of the hottest cities in Spain, and many of its narrow streets use rollover fabric awnings to shade shoppers from the effects of the noonday sun.
Now a spray-on elastomer from Bayer MaterialScience has been used to help provide an area of around 10 000 sq.m of the Plaza de la Encarnación with a gigantic, multifunctional sunshade, spanning the square at a height of more than 20 metres.
The "Metropol Parasol" project to create a group of mushroom-shaped umbrelasl is part of a facelift for this large squares in the historic district of Seville.
For parasol concept of architect Jürgen Mayer H., the most economical solution proved to be a hybrid construction consisting of steel tensioning elements and convex, three-dimensional grid-like structures made of wood.
The wooden structure is made from laminated veneer panels up to 16 m long with a diameter of 7 cm. The total volume of timber is 3500 c.m.
As well as protection from the weather, the 3-mm thick polyurethane coating contributes to the homogeneous appearance specified by the architect for the six giant parasols.
The liquid raw materials were mixed in a mobile spraying machine before spraying, and the coating solidified just a few minutes after application, but remains permanently elastic.
"Baytec Spray is free of solvents, plasticisers and mineral fillers, and offers lasting and reliable protection for wood, concrete and metal," said Joachim Kuerschner, a BMS expert in polyurethane elastomer systems.
The flame-retardant system used in Seville also has very good adhesion to the primer, and gives long-term crack bridging. "Although the spray-on system is water-impermeable, it has very good water vapor permeability," commented Kuerschner, in a BMS statement.
The redesigned square has four levels: first a basement, where archeological excavations are on display. On the next floor - at street level - is a market hall. Above that is the events area, shaded by the giant parasols, containing restaurants, bars and many panoramic pathways.