Technical Documents
Cast Stone, Pre-Cast or Cut Stone?
Choosing the right building materials can be challenging due to the many options available. While cut natural stone is beautiful, it may not always have the necessary structural integrity for building construction, and it’s nearly impossible to duplicate identical pieces exactly.
Precast concrete is usually stronger than natural-cut limestone, but it doesn’t have the same appearance as natural-cut stone. Cast stone, however, solves both of these issues.
Cast stone can be stronger than precast concrete and can be easily cast to produce identical pieces. It is also more weather-resistant than natural stone and can be cast in numerous colors. This makes Cast Stone an excellent substitute for natural cut limestone, sandstone, brownstone, bluestone, slate, granite, travertine, and other natural building stones.
Cast Stone is extremely durable, to the point where U.S. cast stone standards provide for a product with an “infinite life” – which means it lasts for more than 100 years. This durability comes from less water absorption, resistance to freeze-thaw, and abrasion resistance. Because of this, architects and contractors often specify it for construction projects. Most natural stone and precast concrete can’t meet the same standards as Cast Stone, which is why it’s the material of choice for many architectural projects.
Comparison Chart
| Product | Material | Reinforced | Anchorage | Finish | Application |
|---|---|---|---|---|---|
| Cast Stone (04 72 00) | Finely graded Natural stone, sands | Color Pigment: Portland Cement | Yes | Cast in Dowel holes, Anchor Slots, Embedded Hardware, Threaded inserts | Fine Grain Texture Simulates Natural Cut Stone | Architectural Trim, Veneer Facing and ornamentation used in unit masonry construction |
| Architectural Precast (03 45 00) | Coarse aggregate Sand | Color Pigment: Portland Cement | Yes | Cast in Weld Plates, Threaded Inserts, Slots, Dowel Holes | Exposed aggregate, Form liners, Sandblast, Visible bug holes | Architectural panels, columns spandrels and structural elements |
| Limestone (04 40 00) | Sedimentary rock of Calcium Carbonite and/or Magnesium | No | Cut in Dowel Holes Slots | Fine Grain Texture | Architectural trim, facing, ornamentation |
| Calcium Silicate (04 23 00) | Sand and Lime | No | Cut in Dowel Holes Slots | Smooth, Rocked, Press Hammered, Dressed | Architectural veneer facing, usually limited to 2' long |
Physical Properties Comparison Chart
Referenced specifications from the American Society of Testing Materials and the Architectural Precast Association
*Not all compared products have ASTM requirements
| Product | ASTM | PSI (Min) | Air Content Range | Absorption (Max) | Free-Thaw (Durability) |
|---|---|---|---|---|---|
| Cast Stone | ASTM C 1364 | 6,500 | Required for wet cast units | 6% | 5% loss or less @ 300 cycles |
| Architectural Precast | APA 03 45 00 | 5,000 | As Required | 6% | Not Required |
| Limstone Grade II | ASTM C 568 | 4,000 | N/A | 7.50% | Not Required |
| Calcium Silicate | ASTM C 73 | MW 3,500 | SW 5,500 | N/A | 14.0%* | 11.6% | Not Required |
* Assuming average density of 129 lbs/cf