Glass floor

Glass floors are made with transparent glass when it is useful to view something from above or below; whereas translucent glass is used when there is no need to view through. In either case, toughened glass is usually chosen, for its durability and resistance to breakage.

Glass as a flooring material is used in both residential and commercial structures. Special hollow glass blocks known as '"glass pavers" are often used in combination with a metal frame. Glass floors are often lit from below with natural or artificial light, or may be treated as ordinary floor surfaces illuminated from above.

A German manufacturer of squash court floors has diversified into making glass floors for other sports, such as basketball. Their glass floors usually are translucent rather than transparent, and the line markings are indicated by illumination with LEDs below the floor.

On occasion, transparent display cases are built into the floor, such as in the Museum of Sydney (in Sydney, New South Wales, Australia), where the remains of drains and privies are shown in their original context, along with other archeological artifacts.

Usually made of a toughened glass which is also laminated for structural strength, a transparent floor is most commonly used as a tourist attraction. Glass-bottom boats are popular for allowing a better view into the water.

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Wikipedia