**Moisture Mapping** is a crucial step in identifying and mitigating moisture issues within a building. Moisture levels in internal walls need to be carefully monitored to ensure a healthy and safe indoor environment. ### Acceptable Moisture Levels for Internal Walls The acceptable moisture content for internal walls varies depending on the material they are composed of. Generally, the following guidelines are observed: **Material:** | **Acceptable Moisture Content:** ---|---| Gypsum Wallboard | Less than 12% Plaster | Less than 10% Wood | Less than 16% ### What Should Moisture Readings Be for Internal Walls? **Using a moisture meter, the following moisture readings for internal walls are considered acceptable:** - **Below 20% Relative Humidity (RH)**: Dry, no moisture concerns. - **20-30% RH**: Slightly moist, may indicate minor moisture intrusion. - **30-40% RH**: Moderately moist, requires investigation for potential moisture sources. - **Above 40% RH**: High moisture content, requires immediate attention to prevent further damage. **Note:** These moisture readings are general guidelines. Deviations from these values may occur depending on factors such as climate, construction methods, and building materials. It is recommended to consult a qualified professional for specific advice on acceptable moisture levels for internal walls in your particular location.