Test methods simply dictate how materials are tested, while the standard specification stipulates what the test results must be, as well as the ingredients the product must contain. In addition, while simulated stone products are made light in weight so they will work easily on the exterior of other wall material, cast stone weighs approximately the same as natural cut limestone.Ĭast stone has an ASTM standard specification, C 1364, which has substantially different physical requirements than cultured or simulated stone products, which usually reference ASTM test methods. Therefore, simulated stone cannot be used to add to the loadbearing capacity of a masonry wall.
Simulated stone is a lightweight product that is adhered to a structural wall. There are substantial differences between cast stone and simulated stone. These products are manufactured to meet requirements for simulated stone - now under CSI Division 04 42 00, which covers various types of supported stone cladding. Several companies manufacture proprietary stone, products that are used primarily as veneers on other substrate materials such as concrete masonry units. Properly manufactured cast stone has the same or stronger physical properties as most natural dimensional building stone, and should not be confused with other types of simulated stones. Larger units, not generally set by masons in a unit masonry application should be specified as architectural precast concrete under the CSI division 03 45 00. Shop drawings for cast stone should be prepared by a qualified manufacturer to include details and sizes of stones, arrangement of joints, bonding, relationship with other materials, anchoring and proper location in the structure before the manufacturer should be allowed to proceed with the work.įor best practice, concrete manufactured to simulate natural stone used in masonry construction should be specified as cast stone under the CSI division 04 72 00. Masons can place larger elements - such as precast concrete lintels or sills - but that placement is generally not governed by masonry specifications, and hence not within the jurisdiction of the Masonry Standards Joint Committee (MSJC) and other masonry associations. With the weight restriction implicit in hand laying, shrinkage of individual masonry units is not so large as to create local debonding problems. Larger units, when integrated into cavity wall veneer systems, would face new obstacles dealing with the temperature, moisture, movement, volume changes and differentials of materials bonded together with mortar. Since ASTM defines cast stone as a type of architectural precast concrete, the question was formerly too often asked: "What is the difference between cast stone and architectural precast concrete?" Once upon a time, all forms of ornamental precast concrete were made to fill the terms of architectural precast, precast stone, cast stone and other similar terminology, while masons usually performed the setting.īeginning in the 1950s, the sizes of architectural cladding units steadily increased until the concepts of masonry construction would no longer apply. Applications that use cast stone can range from the simplest windowsill to the most complicated classical architecture.Ĭast Stone or Architectural Precast Concrete? The use of a high percentage of durable fine aggregate in cast stone creates a very smooth, consistent texture for the building elements being cast. It can match terra cotta or brick and makes a perfect substitute for brick shapes.
Not surprising, then, cast stone is available in any color and can look like limestone, brownstone, bluestone, granite, slate, travertine or marble. It is made from fine and coarse aggregates such as limestone, marble, calcite, granite, quartz, natural sands, Portland cement, mineral oxide coloring pigments, chemical admixtures and water. Since the early 1920s, cast stone has earned widespread acceptance in the architectural community as a suitable replacement for many masonry materials and for all types of natural cut building stone. The Cast Stone Institute was incorporated in 1927. The product was first used extensively in London in the year 1900, and in the United States around 1920. The earliest known use of cast stone was in the year 1138. It is now properly defined within the construction world as "cast stone masonry" under Division 04 72 00.Ĭast stone is indeed a masonry product that provides architectural trim, ornamentation or functional features to buildings and other structures. 10, 2004, the Construction Specifications Institute (CSI) released a major revision to the 2004 edition of Master Format TM that refined the definition of cast stone. Subscribe to Masonry Messenger to receive the masonry resources and information you need to stay current.