A persistent musty smell in a bathroom is almost never the drains. It is moisture that has nowhere to go, and the textiles are usually where it shows first.
The Underlying Problem
A shower puts a substantial quantity of water into the air of a small room. If that moisture is not removed, it condenses on cool surfaces and soaks into anything absorbent.
Mould needs moisture, a surface and time. Bathrooms provide all three unless something removes the moisture.
Why It Matters Beyond Smell
Worth being clear. Damp and mould in a home are associated with respiratory problems, and the risk is greater for children, older people and anyone with asthma or a weakened immune system.
This is a health issue rather than only a housekeeping one, and persistent mould in a rented property is something a landlord has obligations about in many jurisdictions.
What Actually Helps
- Ventilation during and after every shower, which matters most
- An extractor fan run for fifteen to twenty minutes afterwards
- A window open where there is one
- Wiping down the shower screen and tiles after use
- Hanging towels spread out rather than folded
- Mats that dry between uses rather than staying damp
Weaves designed to release water rather than only absorb it, of the kind at tyuu.net, are addressing the mat side of this; the room still needs air moving through it.
Textiles Are Where It Starts
A mat that stays damp is a permanent reservoir on the floor of a humid room, and it will smell before the walls do.
Hanging mats up between uses, rather than leaving them flat on the floor, makes a substantial difference and costs nothing.
The Extractor Fan
Frequently ineffective and rarely checked. Fans clog with dust, ducting becomes disconnected, and many are simply undersized for the room.
A fan that does not hold a sheet of tissue paper against the grille is not moving enough air. Running it for a period after the shower rather than only during is what actually clears the moisture.
Drying Laundry Indoors
A common hidden cause. Drying washing in a bathroom puts a large amount of additional moisture into the worst possible room.
Cleaning Existing Mould
Small areas can be cleaned with an appropriate product, with the room ventilated and gloves worn.
Never mix cleaning products, particularly anything containing bleach with anything containing ammonia, which produces hazardous fumes. Extensive mould, or mould that keeps returning, indicates a moisture problem that needs fixing rather than repeated cleaning.
Heat the Room
Cold surfaces are where condensation forms. A bathroom that is never heated condenses more.
