Spotting the early signs
Mould rarely arrives with a drumroll. It often starts as faint grey or black speckles around window frames, along grout lines, behind furniture on cold exterior walls, or on the silicone edge of a bath. A musty smell in a cupboard or wardrobe is another early clue. Paint that bubbles or flakes and patches that look damp to the touch can signal moisture that mould loves. Catching it now saves you from bigger repairs later, especially in bedrooms and bathrooms where daily routines add humidity.
If anyone at home has allergies or asthma, pay close attention. Spores can irritate airways and eyes. Early action is kinder to your lungs and your finishes, and it keeps your weekend projects focused on fun, not remediation.
Why mould shows up in the first place
Mould needs three things: moisture, a food source like dust or cellulose, and time. In homes, moisture usually comes from condensation after hot showers, steam from cooking, drying laundry indoors, hidden pipe leaks, or rain finding its way through tired seals and gutters. Cold surfaces such as uninsulated corners and window reveals stay below the dew point, so warm, moist air condenses there. Basements and cellars often sit cool and humid, which is perfect for mould if ventilation is poor.
Address the source as you clean. That might mean repairing a slow drip under the sink, clearing blocked gutters, or running a bathroom fan long enough to actually clear steam. If you want a step-by-step on how to get rid of mould, you can build on the fundamentals below and tailor them to your rooms and materials.
Safety first
Protect yourself before scrubbing. Wear gloves, eye protection, and a well-fitted respirator rated FFP2 or N95. Keep children and pets away. Open windows for fresh air and turn off HVAC systems during cleanup so you do not spread spores through ducts. Bag disposable cloths and sponges after use and seal them before putting them in the bin. Test any cleaner on a small, hidden spot first to check for discoloration.
Cleaning methods that work
On hard, non-porous surfaces
Start by vacuuming loose growth and dust with a HEPA-filtered vacuum. Mix warm water with a few drops of dish detergent and wipe the area to lift grime that shields mould. For disinfection, hydrogen peroxide at 3 percent works well on tiles, sealed worktops, uPVC, and glass. Apply it, allow at least 10 minutes of contact time, then scrub and rinse. Dry thoroughly with a clean cloth. Do not mix cleaning agents. Bleach can lighten stains on some non-porous surfaces, but it is harsh and unnecessary for many jobs, and it can damage metals and textiles nearby.
On porous materials
Drywall, ceiling tiles, insulation, and unsealed wood absorb moisture, so mould can root below the surface. If growth is widespread or the material feels soft, it is usually safer to remove and replace. For minor spotting on painted plasterboard, you can try a light clean with diluted detergent, then let it dry fully and repaint with a stain-blocking primer. Avoid soaking porous materials, and run a dehumidifier to speed drying.
Grout, silicone and bathrooms
Grout and silicone attract soap scum and stay damp, which helps mould cling. Use a cleaner formulated for bathrooms or apply hydrogen peroxide gel where it can sit without dripping. Allow dwell time, agitate with a soft brush, and rinse well. If silicone is deeply stained, replacement is often faster and looks better. Keep the fan on during and after showers, wipe down screens and tiles, and leave the shower door open so surfaces dry between uses.
Room-by-room quick wins
In kitchens, use lids when simmering and run the extractor while cooking and for several minutes afterward. Wipe the underside of window sashes where condensation collects. In bedrooms, pull beds and wardrobes two to five centimeters from exterior walls so air can circulate. Add breathable storage solutions for textiles and avoid packing boxes tight against cold corners. For cellars, store items on shelves, not floors, and choose plastic bins over cardboard which readily feeds mould.
Keep it from coming back
Think habits and humidity. Aim for indoor relative humidity between 40 and 60 percent. Use a hygrometer so you can see patterns across rooms and seasons. Run bathroom and kitchen fans during moisture-heavy tasks and for 15 to 20 minutes afterward. Crack a window for cross-ventilation where it is safe. If you dry clothes indoors, place a dehumidifier nearby and choose a heated drying rack with good airflow.
Fix the building issues that invite moisture. Reseal bath and shower joints, repair dripping traps, and service gutters and downpipes so rain moves away quickly. Add insulation to cold spots and consider thermal liners on notoriously chilly walls. Upgrade single-speed fans to humidity-sensing models for set-and-forget control. On the décor side, choose breathable paints for problem walls and rotate furniture seasonally so you can check for hidden patches.
When to bring in a professional
Large or persistent mould, especially after flooding or sewage leaks, calls for expert help. As a rule of thumb, areas larger than a square meter, repeated regrowth in the same spot, or growth tied to structural damp are signs to get an assessment. A professional can trace hidden leaks, test moisture levels inside walls, and recommend targeted remediation so your DIY efforts are not fighting a losing battle.
Small wins add up. Tackle moisture at the source, clean with the right method for the material, and build routines that keep surfaces dry. Your home will feel fresher and your projects can go back to the creative kind.
