How to Measure Moisture in Buildings

Wood-moisture-equivalent or percent moisture content? Dampness is hazardous before you can see it.

It is important to note that materials do not become visibly damp, and do not feel damp to the touch, until they are quite dangerously damp. Wood, for example, does not feel damp below 30% moisture content (i.e. around 97-98% Relative Humidity), although rot will start to develop at 20% moisture content; thus, dampness is hazardous long before it can be detected by the unaided senses. This is why it is so essential to use a moisture meter to survey for dampness, and making judgements about its severity.
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