Cavity walls were developed to prevent water from penetrating the inner structure, serving as a weather shield. When a hygrometer indicates high humidity in a space, such as a caravan, it may suggest a dampness issue. This guide will help you diagnose damp problems, like black mould growth caused by condensation and salt crystal buildup from water washing salts through walls.
To address these issues, it’s essential to increase ventilation, repair cracked mortar, or replace damaged areas. Additionally, rectifying defects and tanking the wall area below the correct damp proof course level (6 inches or 150mm above outside ground level) into the floor-to-wall notch is crucial.
Several moisture meters are available for detecting dampness. The RDINSCOS Pinless Moisture Meter Mold Detector is versatile for walls, firewood, drywall, and concrete. The DURFICST Moisture Meter features a 3-inch color HD large screen and offers depth analysis for various building materials. These tools are crucial for identifying high moisture areas, which are common in entrance halls and WC areas.
Traditional solid wall structures absorb and release moisture evenly, but issues like penetrating damp can occur due to cracks or leaks in gutters. A moisture meter, when placed against a wall, analyzes the wall’s moisture content, which can vary from 0-20%. However, it’s important to note that damp meters are not always accurate for walls or ceilings and are best used for bare, untreated timber.
For specific product recommendations, the Brennenstuhl moisture detector is effective for determining the moisture content in various materials. The Protimeter Moisture Meter, available for hire, is a handheld digital device ideal for general moisture detection in construction materials and buildings. It displays results on a large LCD, making it easy to read.
When tackling ‘Salts’ drawn out from damp walls, a non-invasive moisture meter can be useful. It reads the moisture content and gives an actual value of the damp level. Other notable products include the Stanley Draper damp detector with 2 prongs and audio alert, and the speedy chemical moisture meter for a quantitative reading of total moisture content in masonry.
It’s also important to look for surface discoloration, such as yellowing, brown spots, or black, furry-looking discolorations, which indicate mold and mildew growth.
