Curing, Sealing, Hardening or Parting Compounds

“Curing compounds leave a film that can interfere with the adhesion of other materials to the treated surface… Their use should be avoided on surfaces that will later be covered with resilient floor coverings…where applicable, a letter of compatibility should be issued prior to the use of a curing compound on a floor receiving a subsequent finish.” (Quote from American Concrete Institute, ACI, publication 302.1R-15, Guide for Concrete Floor and Slab Construction, Chapter 11.2, Methods of Curing.). Any letter of compatibility must come from the manufacturer of the compound.

When curing, sealing, hardening or parting compounds have been used, the following general statements can be made: 

a. If they contain soap, wax, oil or silicone, they must be removed before a resilient floor can be installed. They can be removed by using a terrazzo or concrete grinder, by sanding with a drum sander or by using a polishing machine equipped with a heavy duty wire brush. 

b. There are many materials that do not contain soap, wax, oil or silicone and are advertised as being compatible with resilient flooring adhesives. No specific statement can be made regarding their use or need for removal. Conduct Bond Test to determine the need for removal. If after 72 hours the bond fails, the compound must be removed. 

Curing agents are applied to concrete slabs to retard the escape of water during the initial curing process. Such compounds can remain on the surface of a slab and continue to retard the escape of water during the drying process. They may break down after the floor covering has been installed and the building is in use. This can occur on suspended slabs as well as those in contact with the ground. 

The elimination of excessive free water from the concrete is essential for the formation of a bond between the adhesives, the flooring materials and the concrete. In the presence of excessive free water, water-based adhesives will not set up, and solvent-based adhesives will not adhere. In the case of adhesives already bonded to concrete, the adhesive will be displaced by water if the availability of water is sustained.

Note: In the event of adhesion failure, the responsibility for warranties and/or performance guarantees rests with the compound manufacturer and not with the manufacturer of resilient flooring and/or adhesives.

Updated on May 12, 2023