If you have acrophobia  (people who are scared of heights), then this is not the right place for you. But if not, then you will fall in love with the new glass boxes that on the 103rd floor of Sears Tower. When you are driving in downtown Chicago, you have to stop by Sears Tower and go to the 103rd floor, you will see a small glass room or a “box” at the edge of the building.

Look at this amazing view from the 103rd floor of Sears tower in Chicago. Its breathtaking right? Photo credit Sally Ryan for The New York Times

If you get into the box, you will literally see South Wacker drive 1,353 feet below your feet, its scary I know but according to the manufacturing company ” its safe just enjoy the view”. The transparent room is hanging from cantilevered steel beams above your head. The glass walls are connected to the beams, and to the glass floor, with stainless-steel bolts. New York Times Reported Today.

The box is made out of modified glass to stay strong in hot and cold weather. But the main method engineered used to manufacture this type of room is “Thermal Tempering” and “Chemical Tempering“. In thermal tempering, a sheet of glass is heated and then cooled with air. The surface cools more rapidly than the interior. As the interior cools gradually, it becomes denser and shrinks, pulling the less dense surface into compression. Thermal tempering works well for flat sheets, although it can cause optical distortion to the glass because the sheet sites on rollers while being heated.

In chemical tempering, a glass is put into a hot bath of molten salt. A Chemical reaction causes some sodium atoms on the surface to be replaced with larger potassium atoms from the salt bath. The larger atoms overcrowded and compress a thin surface layer of the glass. Chemical tempering works best for curved or irregular glass and for glass where optical qualities are important.

Tempering puts the surface under compression, so that even more tensile force is needed for cracks to grow. Telegraph reported today.

Photo credit Sally Ryan for The New York Times

“Glass is just another material,” said John Kooymans of the engineering firm Halcrow Yolles, which designed the Sears Tower boxes.

Photo Credit Sally Ryan for The New York Times

Another thing to mention about this rooms is that, each box costs around 40,000$. I am not sure how many of these boxes they made, but the boxes are already open, so anytime you are in Chicago you can visit the breathtaking view.