Mould vs mildew: what's the difference and does it matter?
Short answer: mildew is a kind of mould
Mildew isn't a separate organism. It is the everyday name for mould growth that stays flat and on the surface, usually as a pale, powdery or fine film. When people say "mould" in a home, they tend to mean growth that is darker, fuzzier or thicker, and that has worked its way into the material underneath. So the question that matters isn't really which name fits. It is whether the growth is sitting on top of a surface or living inside it.
How to tell them apart
- Mildew is usually white, grey or pale yellow, looks powdery or dusty, lies flat, and appears on tiles, grout, shower curtains, window seals and the surface of fabrics. It wipes off fairly easily and leaves a clean surface underneath.
- Deeper mould is more often black, dark green or brown, can look fuzzy, raised or slimy, and grows into plaster, wood, grout, leather or upholstery. It leaves a stain after cleaning, comes back in the same place, and often comes with a musty smell.
Colour on its own isn't a reliable guide; our page on what different moulds look like shows why. Behaviour tells you more: how it cleans, and whether it returns.
Why the location matters more than the label
A powdery film on the grout of a shower that is used every day is almost expected. The same film spreading across a bedroom ceiling, or on clothes inside a wardrobe, says the room is holding more moisture than it should, whatever you call it. Growth on porous materials also tends to go deeper than it first appears. On grout, for example, a light surface bloom can sit on top of staining that runs into the joint, which is why deep-cleaning grout and tiles sometimes takes more than one attempt.
Cleaning mildew yourself
Surface mildew on hard surfaces is a normal household job. Open a window, put on gloves and a mask, and wipe the area with a damp cloth and a mould cleaner; don't brush it off dry. Rinse, then dry the surface thoroughly, because leaving it damp invites the next round. Don't mix cleaning products. Washable fabrics can usually go through a normal wash and be dried fully, ideally outside; our guide to saving mouldy clothes covers the details.
When "mildew" turns out to be more
If a patch stains the surface after cleaning, returns quickly, spreads, or sits on paint that is bubbling or plaster that feels soft, you are dealing with more than surface mildew, and wiping alone won't hold. That doesn't automatically mean something serious; it means the material is staying damp and the cause needs finding. Our guide to telling surface growth from a structural problem walks through the signs.
Keeping both away
Mildew and deeper mould need the same thing, so the same habits prevent both: run the bathroom fan during and after showers, open windows fully for a short spell each day, dry laundry outdoors where you can, and keep wardrobes on outside walls less tightly packed. In Cyprus, windowless shower rooms in apartments, seafront flats with humid air and homes heated with portable gas heaters through the winter are where mildew tends to settle first.
When growth has soaked into grout, silicone or plaster, treating mould that has gone below the surface clears it, usually in one visit with no building work. First the cause is found, then the mould is cleared; done the other way round, it tends to return.
Not sure if it's mildew or something worse? book an inspection from €75 and we'll tell you, or call +357 99 759144.