How to stucco over cast concrete fake brick ?
How to get rid of those ugly fake bricks.
Here the concrete was real slick and not very porous. A test is to splash water on the wall to see if it is absorbed. This concrete required chipping to rough up the surface and open pores. The roughing up was done with an electric chipping hammer.
Black water proofing must be chipped. A bonding admixture is used to bond the new mortar to the concrete. This is similar to plastering a swimming pool.
This concrete on this EIFS tear-off was plenty porous with open pits and holes, so it didn't require chipping. An acrylic admixture is essential, at least in the scratch coat.
Flex con is used for additional adhesion. Flex con is an acrylic bonding admixture. We mixed flex con half and half with water and mixed it into the dry mixed mortar. The acrylic not only is adhesive for a good bond, but is resistant to cracks and adds strength.
Stucco is a good way to erase those fake brick you see on new houses. If the concrete is nice and straight, you can get by with a fairly thin coating.