Glass blocks are a special building material made of glass or acrylic. Shaped and laid similarly to brick or concrete blocks, they are available in several different sizes and are commonly used as an alternative to traditional windows, especially in basements. The translucent blocks are also used to construct shower walls, uniquely shaped windows, and are frequently employed in the architectural design of office buildings.
For residential purposes, glass blocks are most commonly used as an alternative to basement windows. Being located at ground level, these windows are considered easy access to a home. Glass block windows are more difficult for would-be thieves to penetrate and thus considered a more secure alternative. Other common residential uses for this building material include shower walls and uniquely shaped and located windows.
Glass blocks are also frequently found in office spaces. They can be used to construct non-load bearing walls, partitions, and windows. The blocks are considered both an architectural element and a practical aspect of design because natural lighting can be filtered in.
There are a variety of designs and sizes of blocks available. They may be opalescent or clear and are also available tinted with hints of various colors. Installation typically involves grout and mortar, but some manufacturers of acrylic blocks use alternative installation methods, such as interlocking PVC joints.
Homeowners can replace existing windows with glass blocks, but should keep in mind that a conversion means that the window can no longer be opened, making it only a source of light. Windows are located in a difficult to reach area or shaped oddly and are non-functional anyway, so the fact that they can't be moved may not be a concern. Glass blocks are also considered more energy efficient than traditional plate glass windows.
These blocks can be found at home improvement stores or custom ordered from any number of manufacturers. Installation can be done by a professional contractor or most door and window companies.