Damp and mould don't just appear out of nowhere but are a direct result of excess moisture in a home. Understanding where this moisture comes from is the first step toward tackling the problem. Equally important is knowing how to spot the early warning signs before a minor issue becomes a major infestation.
Damp is the problem that allows mould to thrive. Think of it as the perfect breeding ground. The causes can be diverse, but they generally fall into a few key categories:
A dripping pipe behind a wall or under a floorboard can go unnoticed for weeks or even months, silently saturating the surrounding materials. This is a common culprit for patches of damp on ceilings, walls, and floors.
This is one of the most common causes of damp, especially in modern, well-insulated homes. Without adequate ventilation, everyday activities like cooking, showering, and even breathing release moisture into the air, this humid air condenses on cold surfaces, leading to condensation damp and, inevitably, mould. Ventilation can be as simple as an open window.
A property's structure is its first line of defence against the elements. If this defence is compromised, water can get in. This includes things like cracked rendering, missing roof tiles, faulty guttering, or damaged window seals. This type of water ingress is often referred to as penetrating damp.
Though it is less common, rising damp is a serious issue. It occurs when groundwater travels up through the brickwork of a building. This happens when the damp-proof course, which is a waterproof layer in the walls, is either absent or has failed. This can typically be spotted as a horizontal line of damp and salt stains a few feet above the skirting board.
Even without structural defects, daily routine can contribute to a damp problem. Drying laundry indoors, using a tumble dryer without a vent, or not using a lid while cooking can all drastically increase the humidity levels in a property, leading to condensation.
The signs of damp and mould are often subtle at first, so it pays to be vigilant. These are:
This is often the first and most noticeable sign. Mould has a distinct, unpleasant odour, similar to a damp basement or rotting leaves. If it can be smelt in a particular room or area, it's a strong indicator that mould is present, even if it’s not visible yet.
This is the most obvious sign. Mould can appear in various colours, including black, green, grey, white, or even pink and orange. It often looks like a fuzzy or slimy patch and can be found on walls, ceilings, around windows, and on fabrics. Don't mistake it for a simple dirt stain, mould growth expands over time.
As moisture seeps into walls, it compromises the adhesion of paint and wallpaper. Bubbling, blistering, or flaking can often occur and the surface may feel cold or damp to the touch.
Look for brown or yellowish water stains on the walls or ceilings. These stains are a clear sign of a water leak from above or within the wall, which will inevitably lead to damp and mould if not addressed.
In severe cases, particularly with rising damp, the presence of moisture can cause plaster to bubble and crumble, which is often accompanied by a white, salty residue. This is a sign that the structural integrity of the wall is being affected.
While not a sign of mould itself, excessive condensation on windows is a clear indication of high humidity in a home. If this moisture isn't dealt with, it will find its way to other colder surfaces, like walls, leading to mould growth.
By understanding the causes and knowing how to identify the signs, you can take proactive steps to protect your properties and your health.
Now that you’ve spotted the signs, what’s next? Arthur can help with that!