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

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).