Page 2 - 2018-07-CFR Volume 118 - The Importance of Wood Flooring Acclimation in a Commercial Setting

Understanding EMC: Critical to Successful Installation The experts at LGM
First, let’s show a very simple table (below) of the relationship of ambi-
ent relative humidity (RH) to equilibrium moisture content (EMC) at 70 specialize in consultation,
degrees Fahrenheit: correction and resolution for
30% RH = 6.2% EMC flooring complaints, claims,
40% RH = 7.7% EMC installation and performance
50% RH = 9.2% EMC
Now that we have this basic relationship to work within the fairly typical issues.
range of indoor RH, let’s look at a real-world example:
Our wood flooring is at a moisture content of 11% (most wood flooring No issue is too big, too small
is typically manufactured in the moisture content range of 6%-9%, so, or too far away for us to
in this example, the wood flooring is higher in moisture content than it
probably should be for the RH in most room environments). The ambi- handle.
ent RH in the room is 40% RH which equates to 7.7% EMC, so what is
the wood flooring going to do over time if installed in this 40% RH envi- All ads are interactive. Just
ronment? We know that the wood’s moisture content is going to even- click on the ad to enter their
tually acclimate with this environment, going from 11% moisture con-
tent to around 7.7% moisture content. The wood flooring is going to website.
shrink in service, probably to an unacceptable level.

The National Wood Flooring Association (NWFA) has a RH guideline
of between 30% and 50% for wood flooring applications (there may be
some small regional variances, but most wood is “comfortable” in this
range). A temperature range of 60°F to 80°F is recommended. Re-
garding engineered (rather than solid) wood flooring, manufacturers
typically pre-acclimate and finish engineered wood at the factory,
which may modify the time it needs to acclimate, if acclimation is even
recommended by the manufacturer.
Whether solid or engineered, always consult the manufacturer's rec-
ommendation/specifications regarding proper acclimation of the prod-
uct prior to installation, and take the NWFA-recommended quantity of
moisture readings on the product before installing. You can consult the
NWFA website to find their detailed recommendations regarding accli-
mating different types of wood under various conditions. If the read-
ings are significantly outside the recommended 6%-9% range, you
may consider rejecting the shipment.
You can check out Wagner Meter’s Wood Moisture Mobile App, which
will help you calculate the proper the EMC for a specific installation.

Page Layout By: Anita S. Drennon

2 Commercial Flooring Report July 2018