Checking the average moisture content of EMCs and structures/areas in wood
So how do you check the EMC of the timber?A good way to do this is to check the %MC of the timber several times over a period of a few days in the environment where it is being installed.Using a timber moisture meter, take readings of the timber's moisture content every few hours until the %MC reading stops changing.
Depending on the original moisture content of the wood, the temperature of the new environment, and the relative humidity of the area, it may take several days for the wood to fully acclimatise to a particular environment. In general, the more significant the difference between the moisture content of the wood and the EMC point of the wood, the longer it will take to fully acclimatise.
Now, you may be wondering how to determine the average moisture content of an area. If you look at the map of the United States here, you can see that most of the United States has an average moisture content of 8 per cent, while some coastal areas have an average moisture content of 11 per cent, and drier desert areas are closer to 6 per cent.
While this gives you a general idea of what to expect, it may be necessary to get more detailed information by taking RH measurements of the area where you are installing your wood.
To get a relative humidity (RH) reading, you'll need a thermohygrometer that can measure temperature and humidity conditions in a large workspace. The RH readings you get from your hygrometer can help you understand what the EMC should be for your wood products on site.
For example, if your RH reading is between 58% and 63% RH, then your average moisture content is about 11%.
Detailed moisture information such as RH and EMC can help you make more informed decisions about carpentry, flooring installation and restoration so you can avoid costly mistakes.
