Micro-Cotta As Alternative Replacement For Terra Cotta

Procedure code:
421404G
Source:
Technical Insight - Kansas State Historical Society
Division:
Masonry
Section:
Terra Cotta Unit Masonry
Last Modified:
08/02/2016

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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).

Last Reviewed: 2017-08-13