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Calculating the Equilibrium Moisture Content

The moisture content of wood in an environment held at the constant conditions of temperature and relative humidity will come to an equilibrium with its surroundings.  The air temperature and relative humidity will determine the equilibrium moisture content (EMC) conditions, and the moisture content of wood in that environment will approach the EMC of the air.  An Excel spreadsheet (titled “EMC Calculate”) is available that will calculate an estimate of the EMC based on the dry-bulb temperature and one of the following: relative humidity; wet-bulb temperature; or, dew-point temperature.

Download the EMC Calculate.xls spreadsheet (or email phil_mitchell@ncsu.edu to get the xlsx version).
Download the article:  Wood Products Notes: Calculating the Equilibrium Moisture Content for Wood Based on Humidity Measurements