Our guide on how to prevent and remove condensation, damp and mould.
If your home is damp, or there are mouldy patches on the walls, this may have been caused by condensation.
Condensation forms when warm moist air meets a cold surface, such as walls, tiles, windows and even clothes. Areas where there is little movement of air such as behind wardrobes and beds if they are placed against an outside wall can be prone to condensation.
When air containing warm moisture rises it can form into water droplets ending up on ceilings and walls in cooler hallways and upstairs rooms often resulting in patches of black mould. All homes have condensation sometimes, especially during cold weather. This is normal and nothing to worry about as long as it clears quickly.
The causes of condensation
Homes are now better insulated with double glazing, modern heating systems, loft insulation and draught excluders. This means that our homes have become more effectively sealed, keeping in moisture produced within the house and providing better conditions for condensation to occur.
There are 3 main causes of condensation:
- Too much moisture produced in your home.
- Not enough ventilation.
- The temperature of your home.
Cooking, washing and drying clothes, taking a bath or shower, even breathing all release moisture into the atmosphere and without adequate ventilation and sufficient background heating you are likely to have condensation in your home.
How much moisture can be produced in your home in one day?
|Washing clothes||1 pint|
|Bath and personal washing||2 pints|
|Two people active for 16 hours||3 pints|
|Cooking and boiling a kettle||6 pints|
|Using an un-vented tumble dryer 6lb load||9 pints|
|Total moisture produced||21 pints|
Producing less moisture
- Cover pans and do not leave kettles boiling.
- Dry washing outdoors on a line, or put it in the bathroom with the door closed and the window open or fan on.
- Vent tumble dryers on the outside (unless they are of the self-condensing type) - DIY kits are available for this.
- Do not use paraffin and portable flueless bottled gas heaters - these produce a lot of moisture and are not permitted under your Tenancy Agreement
Keep your home warm
- Insulation and draught-proofing will help prevent condensation, keep your home warm and cut fuel bills - most of our homes have cavity wall insulation.
- In cold weather, keep low background heating on all day, even when there is no-one at home.
- Most of our properties are also double-glazed. If yours is not, please remember to ask our permission before having this work done.
Ventilating your home
It is important that any air containing a lot of moisture can escape to the outside.
- Keep a small window ajar or a trickle ventilator open when someone is in the room.
- Ventilate kitchens and bathrooms by opening the windows wider.
- Use a humidistat-controlled electric fan - these come on automatically when the air is humid and are cheap to run.
- Close the kitchen and bathroom doors when these rooms are in use, even if you use an extractor fan.
- Get a door closer, as this will prevent moisture from reaching other rooms, especially bedrooms, which are often cooler and more likely to get condensation.
- Ventilate cupboards and wardrobes, an avoid putting too many things into them as this stops air circulation.
- Use a dehumidifier to dry out the air in your home.
To kill and remove mould, wipe down the effected walls and window frames with a fungicidal wash. Please remember to follow the manufacturer's instructions.
Dry-clean mildewed clothes and shampoo carpets. Disturbing mould by brushing or vacuuming can increase the risk of breathing problems. After treatment, redecorate using a good quality fungicidal paint to help prevent mould recurring. (Please note: this paint is not effective if then overlaid with ordinary paint or wallpaper)
The only lasting way to avoid severe mould is to eliminate the problem of condensation and dampness.
The Energy Saving Trust provides information on ways to heat and insulate your home. They can be contacted by telephone on 0800 512 012.
If you have followed all of the steps shown in our guide and are still suffering from excess condensation, damp and mould, please report this to us so that we can investigate the problem further.
Other causes of damp
Not all dampness comes from condensation, it can also come from:
- leaking internal or external pipe work
- faulty roof tiles, guttering or chimneys
- high garden or path levels overlapping the damp proof course
- rising damp because of a defective damp proof course, faulty rendering etc.
These causes of damp can often leave a `tide mark` and can occur any time of year. If this is a problem in your home please contact us to report the problem.