#MAPEITechTip: What about the MVT (moisture vapor transmission) in the concrete slab…how to address before installing the wood flooring?

The key is to QUANTIFY the amount of moisture vapor (MVER is the Moisture Vapor Emission Rate) within the slab this can be done using one of the ASTM test methods, such as the ASTM F1869-16a Calcium Chloride Test that quantifies the amount of moisture vapor emitted from the slab or the ASTM F2170-18 Relative Humidity Test which quantifies the percentage relative humidity (RH) within the concrete slab.  Taking this additional step can help to minimize moisture related issues such as ‘cupping’ and ‘crowning’ resulting in one wood surface to swell or shrink differently than the opposing wood surface.

Depending on the type of hardwood flooring selected, there are three approved methods for installation (always consult both the wood flooring manufacturer and the NWFA Guidelines) nailed down, glued down, or installed as part of a floating floor system, each will have a different method for addressing moisture in the substrate.  When the acceptable installation method is glue-down, MAPEI offers two methods—1.) An all in one moisture control, sound-reduction and wood-flooring adhesive (no moisture limits when installed per TDS) , Ultrabond ECO 995 & Ultrabond ECO 985 2.) A 100% solids epoxy moisture-reduction barrier, followed by an appropriate MAPEI wood flooring adhesive. (ASTM F-3010 )
 

Following these few simple steps we discussed last week and this week will help to minimize the potential for wood flooring failures:
–Proper environment in which to install
–Product acclimation to the installation environment (whatever time it takes to acclimate)
–Addressing MVT in the concrete slab before installation (quantifying moisture)
–Proper product(s) selection and installation
–Floor care after installation