Almost everything that makes a bathroom look tired is one of three things. Limescale from hard water, soap scum from the reaction between soap and that same water, and mould growing wherever moisture sits for long enough.
They need different treatments, and using the wrong one wastes time. Acid handles limescale, alkaline detergent handles soap scum and body oils, and mould needs a product that kills the growth rather than just bleaching its colour away.
The short version
- Acid for limescale, alkaline for soap scum, dedicated product for mould
- Dwell time is the difference between one pass and four
- Never mix bleach with an acidic descaler
- Discoloured silicone usually needs replacing, not cleaning
- The extractor fan does more for a bathroom than any product
Start with the treatments
Apply descaler to the shower screen, taps and tiling, and let it work. Most people wipe it off far too soon and then conclude it did not work.
Remove the shower head if it unscrews and put it into a descaling solution while you clean everything else. A clogged head is the reason for weak or uneven flow, and it clears completely with a soak.
Limescale and soap scum
Limescale is calcium deposited from hard water. It responds to acid, whether that is a proprietary descaler or citric acid, and to repeated applications rather than force.
Soap scum is a different substance: soap reacting with minerals in the water to leave a greasy film. That needs alkaline detergent, which is why a descaler alone often leaves a dull film behind on shower glass.
- Descale first, then degrease, then rinse and dry
- Use a plastic scraper or a non-scratch pad on glass, never wire wool
- Repeat applications beat harder scrubbing on heavy deposits
- Squeegee the screen after each shower to stop it returning
Grout and silicone
Grout is porous, so it absorbs soap, body oils and moisture, and dark lines are often growth within the joint rather than surface dirt. A dedicated mould treatment with dwell time will lift most of it; a stiff brush helps mechanically.
Silicone is a different case. Once mould has grown into the sealant, it is inside the material rather than on it, and no amount of cleaning restores it. The correct fix is to cut the old bead out and replace it, which takes an hour and transforms the room.
Black mould and why it comes back
Mould is a moisture problem before it is a cleaning problem. If it returns within weeks of being cleaned, the cause is ventilation, not a failure of the product.
Check that the extractor fan actually moves air, that it runs long enough after a shower, and that the room is aired daily. Cold external walls, drying washing indoors and blocked trickle vents are the other usual causes.
- Run the extractor during and for a period after showering
- Open windows or trickle vents daily
- Avoid drying laundry in the bathroom
- Wipe the screen and tiles down after use to remove standing water
Surfaces to be careful with
Acidic descalers damage natural stone. Marble, limestone and travertine used as tiling or a vanity top will etch on contact, leaving a dull patch that has to be repolished by a specialist.
Coated surfaces are also vulnerable. Some modern taps have finishes that abrasives strip, acrylic baths scratch easily, and toughened glass shower screens can be marked permanently by aggressive pads.
- pH-neutral products only on marble, limestone and travertine
- No abrasive pads on acrylic, chrome or coated taps
- Test any strong product in a hidden area first
- Rinse thoroughly so no product is left in contact overnight
The parts that get skipped
A bathroom can look clean and still smell, and the reason is nearly always one of a small number of hidden places.
- Shower and basin wastes, where biofilm builds up
- The overflow hole in the basin and bath
- Underneath and behind the toilet, including the fixing caps
- The toilet seat hinges, which lift off on most modern seats
- The extractor grille and its filter or cover
- Bath panel edges and the floor beneath radiators