Wiping off black mould is the easy part. Doing it without spreading spores, and without leaving the cause in place, is where most people go wrong. Here is a safe order of work, and what to do so it does not come straight back.
Clean small patches of mould on hard surfaces with a mould and mildew product, not bleach, wearing a mask, gloves and goggles. Open the window, keep the door to other rooms shut, wipe with a disposable cloth while the mould is still wet, then let the surface dry completely. Bag the cloth and wash your clothes. Absorbent items such as carpets and soft furnishings may have to be thrown away. Cleaning only removes the stain: if you do not find out why it grew, it will be back.
Mould on a wall, window seal or ceiling shows as black, green or grey speckles, sometimes with a fuzzy edge, and often a musty smell. It grows where a surface stays damp, and in homes that is usually the coldest surface in a room, where warm moist air meets it and leaves a film of water.
Energy Saving Trust guidance notes that mould can cause symptoms such as nasal stuffiness, wheezing and eye or skin irritation, and that children, older people and people with skin or respiratory conditions are more at risk. That is a good reason to deal with it properly and promptly, and to speak to a GP if anyone in the home is unwell.
Work through these in order. The first five cover a small patch on a hard surface, such as a painted wall, tiles or a window frame.
Do not mix cleaning products, and do not use bleach as your default. Do not paint over mould and hope: the paint will not fix the moisture behind it. And do not keep soft items that have gone mouldy. GOV.UK guidance says absorbent materials such as carpets, soft furnishings and ceiling tiles may have to be thrown away if they become mouldy.
GOV.UK guidance is blunt on this: simply removing surface mould will not prevent damp and mould from reappearing. The Energy Saving Trust says that if there are no leaks or rising damp, the problem is almost certainly condensation, and that you need to address the root cause. Work out which it is with our guide to rising, penetrating or condensation damp, and check whether a cold spot is behind the patch with our guide to black mould in bedroom corners.
For condensation, the everyday fixes are the ones that cost least: cover pans, run the extractor fan after cooking and bathing, keep trickle vents clear, leave a gap between furniture and outside walls, and dry washing somewhere ventilated. Re-photograph the patch after a few weeks to see whether it has changed.
Winters around Ashford are mild and often wet, so windows stay closed and washing goes on the radiator more than people would like. That is exactly the pattern that feeds mould in older village homes such as those in Great Chart and Charing, where solid walls stay cold, and in more airtight newer homes around Kennington, where moist air has fewer ways out.
A dehumidifier does not clean mould that is already there, and it does nothing about a leaking gutter, a failed seal, rain through pointing or damp rising from the ground. Clean the mould off and fix any leak first. If your home has no loft, a Dryzen system is not an option because the unit is mounted there, and a rented home is not suitable unless the landlord authorises the changes.
If the cause turns out to be condensation across the home, a Dryzen system helps stop the conditions mould and dust mites need. It is a loft-mounted dehumidifier with insulated ductwork to the central area or stairway. Each unit covers up to 150 square metres, extracts about 12 litres a day and costs about 20 pounds a year to run. It has an activated carbon filter and a smart app with temperature and humidity monitoring is included. The warranty is 10 years on parts and labour and 1 year on the compressor. It does not remove mould that is already growing, so clean that off first.
Gold Pack membership (£199 per year) includes remote humidity monitoring of your home and your Dryzen unit and a yearly onsite system check: we monitor the humidity and the unit's performance and alert you if there are any issues.
If you would like a straight answer for your own home, book the free survey. We measure the humidity, check the loft and tell you plainly whether a system would help.
GOV.UK guidance says mould and mildew products should be used in preference to bleach, for health and safety reasons. Whatever you use, wear a mask, gloves and goggles, ventilate the room and follow the label.
Cleaning removes the growth but not the damp that fed it. Condensation on a cold surface, a leak or poor airflow behind furniture will let it return. Photograph the patch, fix the likely cause, then check again after a few weeks.
GOV.UK guidance says larger areas should only be addressed by qualified professionals. Get advice if mould covers a large area, keeps returning, sits with a damp or stained wall, or if someone in the home is unwell.
Sources: GOV.UK: Understanding and addressing the health risks of damp and mould in the home; Energy Saving Trust: How to get rid of damp
Last reviewed 2026-10-13. General guidance only; this is not a survey of your home.