Damp, mould and condensation in private rented accommodation

Private rented property licensing

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Condensation is one of the most common causes of mould growth and is caused by a combination of excess moisture in the air and poor ventilation. 

Effects of excess moisture

When excess moisture lands on cold surfaces such as windows and walls it can, if left, turn into black mould and have an unpleasant odour.

When more severe, condensation and mould can affect walls, or it even may soak into wallpaper, paintwork and furniture. It can often be found in corners of rooms where there is little airflow. Damp and mould are more likely to be a problem in the cold winter months.

Types of damp

Condensation should not be confused with damp. Although condensation can create damp in the home, increasing the chance of mould growth, damp can also be a result of other issues.

There are different types of damp and that can lead to mould growth.

Leaks/penetrating damp

Dampness can be caused by water leaking through internal damaged pipework, a failed stopcock or via faulty bath/window seals. Penetrating damp is a result of external moisture entering the home through its external structure and is made worse during periods of heavy rainfall. This is often a result of gaps in brickwork, roof or windows, and if there are structural issues (e.g. broken guttering, roof defects or window frames).

Rising damp

Dampness that is mainly seen in basement level and ground floor properties, with moisture rising from the earth effecting flooring, plaster, wallpaper and skirting boards which is caused by a defective or non-existent damp proof membrane. Rising damp is likely to occur throughout the year but will be more prominent during colder months.

Preventing condensation and mould

The following steps can help prevent condensation and mould:

Heat your home

Damp and mould are more likely to occur in the cold winter months, so it is important to try to maintain a warm environment - constant low heating is better than extreme hot and cold.

The occurrence of damp and mould may be also exacerbated due to the current fuel and cost of living crisis as residents struggle to meet the high cost of heating their homes. If you are worried about the cost of living crisis and would like some advice and support visit the Cost of Living Hub, which contains information on the support that is available for residents.  

Keep your home ventilated

The single most important step is to ensure good ventilation, especially in kitchens and bathrooms. Open windows slightly, use an extractor fan when using these rooms and do not cover air vents. These steps will help to direct moisture outside the house and prevent condensation in your home.

Close kitchen and bathroom doors when these rooms are in use to prevent steam escaping into colder rooms.

Reduce moisture levels

To reduce moisture levels in your home:

  • Dry clothes outside if possible, use a condenser tumble dryer or make sure the air vent goes outside
  • Cover pans when cooking
  • Open windows when running a bath/showering
  • Clear window sills of clutter, so it's easier to open windows
  • Leave a gap between furniture and walls

Vacuum regularly

Vacuuming helps to remove mould spores and dust. Mould feeds on dust. Do not brush sills etc, as this spreads spores.

Remove excess moisture

Wipe windows and sills with a clean dry cloth each morning to remove any water that has settled overnight.

Dealing with condensation and mould 

If you already have condensation and mould in your home, there are things you can do to avoid it getting worse.

Condensation

Use a dry cloth to wipe away moisture from windows, sills, mirrors or walls each morning.

Remove small mould patches

You should first contact your landlord or managing agent if mould patches begin to develop in your property so that your landlord can take the necessary action to resolve the problem. However, if you do decide to remove mould yourself, make sure you wear gloves and follow these steps:

  • Wash the mould growths with bleach and water (one part bleach to four parts water)
  • Clean with a mould spray (fungicidal spray)
  • Leave surfaces to dry with plenty of ventilation
  • Do not reuse cloths infected with mould/spores as this will spread the problem

Help with damp and mould

If you have problems with damp and mould in your rented property you should contact your landlord or managing agent first.

Contact your landlord

Contact your landlord or managing agent immediately, in writing, and report the issue to them, keeping a copy for yourself.

Tell your landlord or agent:

  • Exactly what the problem is
  • Exactly where there problem is
  • What you have done already to try to solve the problem
  • That you need them to help

You may find it useful to use this template letter from Shelter.

Report a problem to us

If you still have problems with condensation, damp and mould after reporting the issue, or your landlord is not responding to your requests, then you should contact us to report a problem

We will assess your report within five working days (except for emergencies, in which a quicker response will be given). We may inspect and assess whether your home is safe. If we need to contact your landlord to require repairs or alterations to be carried out, we will do this as soon as possible after assessing what needs to be done.

Outcome of assessment

The outcome of the inspection will determine the action we will take. For example, if we find conditions that are a risk to your health, we may issue a notice to the landlord. If the landlord fails to comply with a notice, we may fine or prosecute your landlord.

In severe situations, we may make repairs ourselves or make an order prohibiting your landlord from letting the property or a part of the property. We will keep you informed of the progress of any action we take.