Micro-Cotta As Alternative Replacement For Terra Cotta
- CSI Division:
- Division 4- Masonry
- Terra Cotta Unit Masonry
- Last Modified:
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This standard includes general information on an alternative material for use in the replacement of severely deteriorated terra cotta ornament. Micro-cotta is a lightweight, polymer-based composite concrete manufactured by Patentech Corporation of Sugar Grove, Illinois. It is a replacement alternative suitable for reproducing the appearance of terra cotta, cast stone, slate and cast iron. The characteristics of micro-cotta as a replacement for terra cotta are believed to be superior to more traditional replacement materials such as cast stone, fiberglass, and even replacement terra cotta. Some characteristics of micro-cotta include the following:
- Polymer-based micro-cotta utilizes a finer aggregate than cement-based concrete
- Capable of reproducing detail with sharp definition
- Greater resistance to weathering:
- Lower absorption rate (1% compared to 13% for concrete and 7% for terra cotta)
- Color value and tone of material is relatively stable during aging process unlike that offiberglass laminates or cast stone
- Micro-cotta's resistance to cracking and spalling compared to that of terra cotta is not conclusive.
- Micro-cotta is lightweight (70 lbs./cubic foot)
- It is 50-70% lighter than masonry products and, therefore, substantially less expensive to install. Micro-cotta is most commonly produced from a mold of the original unit. It is anchored using standard conventional masonry anchors (preferably stainless steel, as recommended by Patentech Corporation).