ER-921 Anti-Vap

Concrete Finishing Aid

ER-921 is a surface-active agent used to reduce the water evaporation rate from the surface of newly laid concrete. It is designed to form a thin film to reduce rapid moisture loss from the concrete surface. ER-921 is spray applied in diluted form to fresh concrete flatwork to reduce the tendency for surface plastic cracking to occur. ER-921 aids and improves the workability and finishing characteristics of the concrete surface. ER-921 also helps extend the surface workability time for a given set of weather conditions.


  • Use ER-921 as an evaporation retarder for concrete flatwork surfaces when the evaporation rate exceeds the bleeding rate. Recommended for use on all concrete surfaces except dry shake hardeners and toppings.

Comparison with traditional systems:

CharacteristicsTraditional SystemsGeoplast Reusable Formwork
Hindrance-Modular system
ResistanceLimitedUp to 60 kN/m2
Concrete adherenceRequires dismantling agentsBeing made of plastics, GEOTUB PANEL does not stick to concrete
Protection10%The best protection for the columns until the end of the operations
PlumbingRequires long operations and it is often inaccurateQuick and accurate thanks to the external structure that allows easy shoring and plumbing
Dismantling agentsRequiredNot required. Everitt Site Supplies recommend 'Kleen Kote' protection and release formula to maintain your forms in top condition.