User:Kalkot/sandbox

Potential Edits of Existing Text
Glass brick, also known as glass block, is an architectural element made from glass. The appearance of glass blocks can vary in color, size, texture and form. Glass bricks provide visual obscuration while admitting light. The modern glass block was developed from pre-existing prism lighting principles in the early 1900s to provide natural light in manufacturing plants. Today glass blocks are used in walls, skylights, and sidewalk lights.

Appearance
The texture and color of glass blocks can vary in order to provide a range of transparency. Patterns can be pressed into either the inner void or the outside surface of the glass when it is cooling in order to provide differing effects. Glazes or inserts may also be added in order to create a desired private or decorative effect.

Wall Blocks
Glass blocks can provide light and serve as a decorative addition to an architectural structure, but hollow glass blocks are non load-bearing unless stated otherwise. Hollow glass wall blocks are manufactured as two separate halves and, whilst the glass is still molten, the two pieces are pressed together and annealed. The resulting glass blocks will have a partial vacuum at the hollow center. Due to the hollow center, wall glass blocks do not have the load-bearing capacity of masonry bricks and therefore are utilized in curtain walls. Glass block walls are constrained based on the framing in which they are set. If a masonry or steel frame exists, the maximum area of the wall can be 144 ft2, whereas the maximum area without a frame is 100 ft2.

Skylights and Sidewalk Lights
Glass blocks used in flooring are normally manufactured as a single solid piece, or as a hollow glass block with thicker side walls than the standard wall blocks. These blocks are normally cast into a reinforced concrete gridwork or set into a metal frame, allowing multiple units to be combined to span over openings in basements and roofs to create skylights. Glass wall blocks should not be used in flooring applications because the way in which they are manufactured does not allow them to support a load.

Falconnier
Modern glass bricks were preceded by Falconnier Hollow Glass Bricks in the late nineteenth century. Falconnier Bricks were blown glass bricks available in multiple colors and were formed in molds while the glass was molten. The Falconnier bricks could be used for walls or roofs and were joined together with wire and cement. The suggested use for Falconnier glass bricks was in greenhouse construction due to the non-conductivity of the glass for temperature control and lack of porosity of glass for moisture control. Falconnier bricks were touted for not tarnishing, trapping dust, or retaining water.

Prisms
Vault lights in sidewalks, which utilized prism lighting, were one of the first steps towards the modern hollow glass brick. At the end of the nineteenth century glass prism became a popular way to diffuse light into spaces that would otherwise be difficult or unsafe to light via flame-based oil lamp s (i.e. basements underneath sidewalks).

New Examples
Österreichische Postsparkasse in Vienna, Austria by Otto Wagner

Raphael's Refuge, outside of Flatonia, Texas

Glass Block Talk Page Intro
Hi,

I would like to contribute to this page. I've listed some references to help with the history, which seems to be missing. Adding historical uses may be helpful since the material dates back to the nineteenth century. I also recall some architects used to integrate them into their flooring systems as a health benefit for workers (e.g. Otto Wagner's Österreichische Postsparkasse), although I'm unsure of sources other than the Postsparkasse's museum. Does anyone know of any?

Other potential sources:

Explains the different standard sizes and installation methods.

Explains a manufacturing process.

An early 20th century summary of glass brick use.

The use today.

Describes early color blown glass bricks. Kalkot (talk) 03:53, 9 November 2017 (UTC)