Keep your home ventilated
Ventilate rooms after showering or cooking

A home with moist air uses more energy to heat and can cause bills to rise. It takes longer to heat damp air, and it cools down quicker.
This moisture increases the chance of condensation – the water that forms on your windows and walls. Repeated condensation over time can lead to damp and mould, which may mean people in the home are more likely to have respiratory problems, respiratory infections, allergies or asthma. Damp and mould can also affect the immune system.
That’s one reason why it is so important to keep your home ventilated, particularly after showering or cooking on the hob. Of course, ventilating your house properly will also save you money.
It can help to keep a close eye on humidity in your home. Humidity is a measurement of how much water vapour is present in the air. You can measure it using a hygrometer.
Ideally you want to have a humidity reading between 30% and 60% (in summer this is 40-60%, in winter 30-50%). It doesn’t take much for humidity levels in the home to soar, particularly when showering or cooking, so it’s important to know how to reduce the moisture in the air.
The easiest way to reduce moisture in the air is to open a window.
This helps to keep your home ventilated.
Even if it’s cold outside, opening a window for just a few minutes is important to reduce the chance of having condensation and mould in the home.
In a room where you’ve opened a window, close the door to stop the cold air from moving into the rest of the house.

Our Green Doctors have identified helpful impartial advice on what can really make a difference in reducing bills and saving energy.
Download our supporting home resources – our action plan, our meal and shopping planners, and our stickers – to help you make changes which stick.
Using extractor fans
Extractor fans are also useful for reducing moisture in a room.
It’s important to turn them on during and / or after showering or cooking to reduce the risk of damp, mould and condensation.
Make sure the fan is unobstructed. Remember, extractor fans don’t let in the cold, they simply remove moisture from the room.
Another option, particularly for homes without extractor fans, is to purchase a dehumidifier. These can feel like an expensive one-off purchase but they can be effective in reducing humidity in your home. They can also help reduce the risk of damp when drying clothes indoors.

Make a plan. Stay warm. Save energy.
- Place one of our stickers near the hob to remind you to ventilate when cooking.
- Place one of our stickers near the shower to remind you to ventilate the room.
