Signs of damp and mould

Sometimes damp is easy to spot. It might be a dark or wet patch on a wall, floor or ceiling.

It could mean a bigger problem if it does not dry out quickly or keeps coming back.

Some signs of damp can be:

• paint or wallpaper peeling off

• walls feel wet when you touch them

• wood in your home feels wet or spongy

• a musty smell, like soil or a blocked drain

Where does mould grow?

Mould can grow anywhere that might be damp, including walls, floors and ceilings.

It is common around windows and more likely on external walls. It also often grows around baths, showers and sinks.

It also grows behind furniture and inside wardrobes.

What does mould look like?

There are many different types of mould. It can be white, green, black and other colours.

Mould can be furry, or look like stains on walls. Sometimes it looks like groups of little dark spots.

Back to top

There can be lots of different reasons for damp.

You might have to deal with some types of damp, for example, try to reduce condensation.

But damp in your home might mean there's a problem with the structure. This is usually your landlord's responsibility, and might get worse if it's not dealt with.

The main types of damp are:

• condensation

• penetrating damp

• rising damp

• damp from leaks and floods

Condensation

This is the most common type of damp. It happens when the air in your home becomes very wet. When wet air touches something colder, like a window or outside wall, condensation forms.

Condensation appears more in winter because cold air holds less water.

It happens most in kitchens, bathrooms and other places where you use hot water. You can also find it on bedroom windows and walls, especially in cold weather.

Some of the main causes of condensation are:

• cooking

• showers and baths

• not enough ventilation

• cold conditions in your home

But condensation might be a sign your home is damp for other reasons. For example, a leaking roof or broken pipe can cause the air in your home to become too wet.

Find out more about how to deal with condensation.

See an image of what condensation can look like

This window has condensation on the glass. Mould is starting to grow on the wall around the window.

It might help to:

• wipe condensation off the window regularly

• open the window more often

Tell your landlord if there's condensation in your home.

They should check if a bigger problem is making things worse. For example, a leak or not enough insulation.

Penetrating damp

Penetrating damp happens when water gets through the walls. Usually it's water from outside getting into your home.

Sometimes mould grows where the damp is. But sometimes it just causes damp patches and flaking paint or peeling wallpaper. Mould might grow somewhere else because of condensation from the damp.

Common causes can be:

• blocked guttering

• broken pipework outside

• damage to outside walls, like cracked bricks

You might notice the problem gets worse in bad weather.

See an example of what penetrating damp might look like

Water is soaking through damaged bricks on the outside. This is making damp patches on the wall.

Mould is starting to grow in the damp patches.

This kind of damp often gets worse in bad weather.

The landlord has to fix the damaged brickwork and deal with the damp and mould inside.

Rising damp

Rising damp is when water from the ground soaks up into walls.

It usually appears on the ground floor. Sometimes you can see a long wet patch rising up walls from the floor.

Rising damp is a lot more common in older homes. Older homes are less likely to have a 'damp proof course', which stops water getting into walls.

A damp proof course is often a row of darker coloured or blue bricks near the ground. Sometimes it is a waterproof layer put between bricks. In older properties it can look like a row of holes where something was injected into the wall.

See an example of rising damp

Rising damp has made a wet band at the bottom of these walls.

Paint is starting to bubble and flake on one wall.

The damp area is around an electric socket. This could be dangerous.

The landlord needs to treat the rising damp. This could be a big job that takes a long time.

Damp from leaks and floods

This type of damp can appear anywhere there are problems with pipes or drainage. It often happens in rooms below kitchens and bathrooms.

If a leak is fixed quickly and the room is dried out properly there is less chance of long term problems. But some leaks are hard to spot, for example, in pipes under the floor or in walls.

See an image of how damp from a leak might look

A leak has made the ceiling damp. The damp is now spreading down the wall too.

Mould has started to grow where it is damp.

The landlord needs to fix the leak. Then the ceiling and wall can dry out, and the mould can be treated.

Back to top