Frequently Asked Questions

Biomeiler (1)

The range of Moisture Content (MC) is from a theoretical 0% MC to well above 100% MC for freshly cut timber depending on the time of cutting. for example MC of 200% means the piece of timber holds twice its own (dry) timber weight in form of water.
Timber is usually considered "dry" at 19% MC. Indoors timber will settle at a moisture content of around 8-14% MC depending on temperature, room climate and general humidity levels; healthy levels would be around 45-60% r.H. In the open covered timber may have a MC of around 12-18% depending on the season.

Quite different to Moisture Content (MC) is the Water Content (WC in %):

Moisture Content Water Content Water in g/1kg   Moisture Content Water Content Water in g/1kg
20% 17% 167   30% 23% 231
40% 29% 286   50% 33% 333
60% 38% 375   70% 41% 412
80% 44% 444   90% 47% 474
100% 50% 500   110% 66.7% 667

From Wikipedia:

The moisture content of wood is calculated by the formula (Siau, 1984):

moisture content = m_g-m_{od} \over m_{od} (1.1)

Here, m_g\; is the green mass of the wood, m_{od} \; is its oven-dry mass (the attainment of constant mass generally after drying in an oven set at 103 +/- 2 °C for 24 hours as mentioned by Walker et al., 1993). The equation can also be expressed as a fraction of the mass of the water and the mass of the oven-dry wood rather than a percentage. For example, 0.59 kg/kg (oven dry basis) expresses the same moisture content as 59% (oven dry basis).

moisture content = Weight When Cut - OvendryWeight \over OvendryWeight x100%

Where the wet weight is the weight of the original 'wet' sample and the dry weight being the weight of the sample after drying in an oven. Moisture contents being expressed as a percentage.


Your rating: None Average: 5 (1 vote)