Moisture Mapping Guide to Wood Moisture Content

Wood Moisture Content

Wood moisture content refers to how much water exists within the wood. It is expressed as a percentage of the oven-dry weight of the wood. Wood moisture content is influenced by its surroundings, such as temperature and relative humidity.

Preferred Moisture Content for Treating Wood

When treating wood, it is crucial to ensure the moisture content is within the optimal range to guarantee effective penetration and adherence of the treatment. The preferred moisture content for wood treatment varies depending on the treatment type and wood species. * **Pressure Treatment:** For pressure-treated wood, which is used in outdoor applications like decks and fences, a moisture content between 15-19% is ideal. This moisture level allows for proper preservative penetration and prevents excessive shrinking or swelling. * **Brush-On or Spray-On Treatments:** If using brush-on or spray-on wood treatments, a moisture content below 15% is recommended. Higher moisture levels can impede the treatment's absorption into the wood. * **Certain Wood Species:** Some wood species have specific optimal moisture content ranges. For example, cedar and redwood perform best with moisture levels below 12%, while hardwoods like oak and maple can tolerate moisture content up to 15%. Maintaining the appropriate moisture content during treatment is essential for successful and durable wood protection.