User:Thenightmancometh/sandbox

Week 2:

Sources for terrazzo:

Hornobostel, Caleb''. Construction Materials: Types, Uses, and Applications'', (John Wiley & Sons, New York: 1978), pg. 731-735.

Jester, Thomas C., and Michael A Tomlan. Twentieth-Century Building Materials: History and Conservation.

"Deterioration of Terrazzo", Journal of Architectural Engineering. Volume 17, Issue 2, pp. 51-58.

Chabbi, Amel, "Restoring a 20th Century Terrazzo Pavement: A Conservation Study of the Floor Map of the New York State Pavilion Queens, New York." Master's Thesis, University of Pennsylvania, 2004.

Thorkelson, Anne, "An Approach to Conservation and Presentation of the Terrazzo Map Pavement of the New York State Pavilion in Queens, New York." Master's Thesis, University of Pennsylvania, 2007.

Johnson, Walker C. "Terrazzo." in Twentieth-Century Materials: History and Conservation, edited by Thomas C. Jester. New York: McGraw Hill, 1995.

L. Del Turco and Bros. Modern Mosaic and Terrazzo Floors; a Handbook on the Improved Method of Laying Terrazzo Floors with Metal Dividers, Precase Terrazzo Base, Treads, etc. Marble Mosaic Floors; Full Size Color Samples and Floor Designs. Harrison, N.J.: L. Del Turco and Bros., Inc., 1924.

The National Terrazzo and Mosaic Association. "Restoration of Terrazzo Finish." http://www.ntma.com/05_specification.php.

Olin, Harold B., John L. Schmidt, and Walter H. Lewis. "Terrazzo." in Construction Principles, Materials, and Methods. 6th Edition ed. New York: Van Nostrand Reinhold, 1995.

Polson, Mary Ellen. "Terrazzo." Old House Journal 28, no. 5 (2000): 88

Week 3 Week 4
 * Terrazzo Proper
 * 1) The terrazzo form used today derives from the Venice with the pavimento alla Veneziana (Venetian pavement) and the cheaper seminato.
 * 2) Pavimento alla Veneziana had workers place marble fragments next to each other while seminato simply had larger marble chips tossed into the cement that was then ground and polished.
 * 3) Together, these methods create the generic form of terrazzo that involves pieces of stone that are bonded to a cement bed.
 * 4) Terrazzo was first introduced in the United States in the late 1890's, but did not achieve popularity until the 1920s.
 * 5) Until then it was hand polished with a long handled tool called galleras.
 * 6) Due to its likelihood of cracking, terrazzo was used at a small scale rather than the large expanses we see today.
 * 20th Century
 * 1) Two inventions resulted in a rise in popularity:
 * 2) The invention of divider strips by L. Del Turco and Bros. in 1924 contained the cracking of terrazzo. This invention made it a durable and reliable material that was less likely to crack. Additionally, they served as guides to the installers when they were working with different colored terrazzo.
 * 3) The electric grinding machine and mechanization of the production process cut down on costs and time making terrazzo an affordable flooring option.
 * 4) Art Deco and Moderne styles from the 1920s to 1940s favored terrazzo with the dividers allowing for straight or curved lines that increased the decorative potential.
 * 5) The popularity of terrazzo lead to an increase in installers in the 1920s. The National Terrazzo and Mosaic Organization was formed in 1931 to further professionalize the practice of terrazzo installation.
 * 6) One of the most well known example of terrazzo is the Hollywood Walk of Fame. Created in 1958, the walk honors celebrities in the form of a terrazzo star that displays their name.
 * Components
 * 1) At its most essential, terrazzo is composed of cement and marble chips.
 * Types and Systems
 * 1) Terrazzo installation includes both bonded and unbonded methods. Bonded systems include: bonded underbed, monolithic, chemically bonded, and the most recent, thin set method (epoxy-resin). Unbonded includes the sand cushion method which uses wire reinforcing, an isolation sheet, and sand dusting that absorbs any movement from the concrete slab.
 * Deterioration
 * 1) Cracking is the most common form of failure and is typically caused by the structural system that supports the terrazzo topping rather than the material itself.
 * 2) Contact with alkalis or acids can deteriorate the bonding agents used in terrazzo.
 * 3) If a large portion of the flooring must be replaced due to cracking, it must first be cut out. After which, the structural subsurface should be examined before attempting to find a compatible replacement.
 * 4) Replacement terrazzo must achieve a continuous look by having the same colored marble chips as the rest of the floor. There are common terrazzo formulas that can be acquired. Otherwise, a "braketing" system can be used which attempts to recreate the original formula by mixing and matching different chips.

Terrazzo proper
Although the history of terrazzo can be traced back to the ancient mosaics of Egypt, its predecessors come from Italy. The form of terrazzo used today derives partly from the 18th century pavimento alla Veneziana (Venetian pavement) and the cheaper seminato. Pavimento alla Veneziana had workers place marble fragments next to each other in a mortar base. Terrazzo is also related to the technique seminato for which workers tossed larger marble chips into the cement that was then ground and polished. Together, these methods create the generic form of terrazzo that involves pieces of stone that are bonded to a cement bed. Terrazzo was first introduced in the United States in the late 1890's, but did not achieve popularity until the 1920s. Until then it was hand polished with a long handled tool called galleras. Due to its likelihood of cracking, terrazzo was used at a small scale in comparison to the large expanses we see today. Two inventions resulted in its rise in popularity: divider strips and the electric grinding machine. The invention of divider strips by L. Del Turco and Bros. in 1924 contained the cracking of terrazzo by allowing the material greater space to expand and shrink after instillation. This invention made terrazzo a durable and reliable material in addition to allowing for further design work within the floor. Installers use the dividing strips as guides when they work with different colored terrazzo. The electric grinding machine and mechanization of the production process cut down on costs and time making terrazzo an affordable flooring option.

Art Deco and Moderne styles from the 1920s to 1940s favored terrazzo with the dividers allowing for straight or curved lines that increased the decorative potential. The popularity of terrazzo lead to an increase in installers in the 1920s. The National Terrazzo and Mosaic Organization was formed in 1931 to further professionalize the practice of terrazzo installation. One of the most well known examples of terrazzo is the Hollywood Walk of Fame. Created in 1958, the walk honors celebrities in the form of a terrazzo star that displays their name.

Types and Systems
Terrazzo installation includes both bonded and unbonded methods. Bonded systems include: bonded underbed, monolithic, chemically bonded, and the most recent, thin set method (epoxy-resin). Unbonded includes the sand cushion method which uses wire reinforcing, an isolation sheet, and sand dusting that absorbs any movement from the concrete slab.

Deterioration
Cracking is the most common form of failure and is typically caused by the structural system that supports the terrazzo topping rather than the material itself. Contact with alkalis or acids can deteriorate the bonding agents used in terrazzo. If a large portion of the flooring must be replaced due to cracking, it must first be cut out. After which, the structural subsurface should be examined before attempting to find a compatible replacement. Replacement terrazzo must achieve a continuous look by having the same colored marble chips as the rest of the floor. There are common terrazzo formulas that can be acquired. Otherwise, a "braketing" system can be used which attempts to recreate the original formula by mixing and matching different chips.