Bathroom Mould Removal in Liverpool

Why does mould grow in bathrooms?

A hot shower releases a large amount of water vapour in a few minutes. When that warm, moist air meets anything colder, such as the ceiling under a cold loft, an outside wall, a window frame or the tiles behind the bath, it turns back into water. If the room stays damp for hours afterwards, mould spores that are always present in the air settle on those wet surfaces and start to grow. Soap residue and skin cells give them something to feed on.

Most bathrooms we see have at least one of these contributing problems:

• An extractor fan that runs but moves far less air than it should, often because of a long or crushed flexible duct, a clogged grille or a fan that was undersized to begin with.
• No fan at all, or a fan on the light switch with no overrun, so it stops as soon as the light goes off.
• A door with no gap underneath, so replacement air cannot get in and the fan struggles.
• A window that stays shut in winter, understandably, because the room is cold.
• A cold outside wall or ceiling with little or no insulation behind it.
• Low background heating, which leaves surfaces cold enough for condensation to form.

Bathrooms in Liverpool homes

Many Victorian and Edwardian terraces across the city had their bathrooms added later, often in a single-storey or two-storey back extension. That puts the bathroom on cold outside walls on two or three sides, sometimes under a flat or lightly insulated roof. It is one of the most common places we find mould in older houses in areas like Anfield and Walton. In flats, including converted houses and post-war blocks, bathrooms are often internal rooms with no window at all, so the extractor fan is the only way moisture can leave.

What does bathroom mould removal involve?

1. Look and measure. We note where the mould is and take humidity and surface readings. We check the extractor fan’s performance, the duct route where we can see it, the door gap and the window, and we look for leaks around the bath, shower tray, pipes and the ceiling above.
2. Protect the room. We protect surfaces and, for larger areas, contain the work so spores are not spread through the house.
3. Clean and treat. Mould on tiles, painted walls and ceilings is cleaned off and treated with a suitable mould-removal product.
4. Remove what cannot be cleaned. Silicone sealant with black mould growing inside it cannot be cleaned; it is cut out and replaced. The same applies to badly affected grout, mouldy wallpaper and, sometimes, sections of plasterboard ceiling.
5. Fix the cause. Usually this means improving extraction, which may involve a new or better-ducted fan, a humidity-controlled fan or adding an undercut to the door. Leaks are repaired and cold surfaces dealt with where practical.
6. Finish. Once surfaces are dry, the room can be decorated with a suitable bathroom or anti-mould paint.

Is your extractor fan good enough?

Approved Document F (2021 edition) sets a minimum intermittent extract rate of 15 litres per second for a bathroom in England. A fan’s box may quote a higher figure, but the air it actually moves once fitted can be much lower if the duct is long, flexible, kinked or vents into the loft rather than outside. Installers of replacement fans are expected to check the flow they achieve. We often find fans that hum away but barely lift a sheet of tissue.

Options include a properly sized fan with a short, smooth duct to outside, a humidistat fan that switches itself on when humidity rises, or a continuously running low-rate fan. Any electrical work in a bathroom is notifiable under Part P and is carried out by qualified electricians with the correct paperwork. Our extractor fan installation page explains the choices in more detail.

Small patches: what can you do yourself?

For a small spot of mould on a hard surface, wipe it with a damp cloth and a suitable mould-removal product, following the label, with the window open and the fan on. Never mix cleaning products, especially bleach with anything else. Afterwards, run the fan or keep the window open for a while after every shower and wipe down the screen and tiles if you can.

If the mould covers a large area, more than about a square metre, keeps returning within weeks, is in sealant or grout, or is in a home where someone has asthma, a breathing condition or a weakened immune system, it is worth having it looked at. Speak to your GP or NHS 111 if you are worried about symptoms.

When bathroom mould is not just condensation

Mould that sits in one spot rather than across the ceiling, or that comes with brown staining, swollen boards or a musty smell, can point to a leak. Failed seals around a shower tray, a weeping waste pipe or a slow leak from the floor above can all keep a patch wet. Damp low down on an outside wall may be something else again. We check for these before quoting so that you are not paying to clean mould that will come straight back. If you want to compare symptoms, our damp and mould problems guide sets them out side by side.

What affects the cost?

We give a written quote after the visit. The main factors are how much of the room is affected, whether sealant, grout or plasterboard need replacing, whether a new or upgraded fan is needed and how far the duct must run, any leak repairs, and whether you want us to redecorate afterwards. Rented homes may need a written record for the landlord or agent, which we can provide.

Bathroom mould in rented homes

If you rent, tell your landlord or agent about the mould in writing with photos. Bathroom ventilation is part of the building, and the 2023 government guidance on damp and mould says landlords should tackle underlying causes rather than ask tenants to keep cleaning. Landlords and agents can ask us for photo-backed notes; see our landlord damp and mould service.

Bathroom work is one part of our wider mould removal in Liverpool. If mould is also showing in bedrooms or behind furniture, the cause may be whole-house condensation rather than just the bathroom, and we will look at that too as part of our professional mould removal service.