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Condensation
The most common kind of damp in our homes is condensation.
Although not always a problem by itself, condensation can lead to black mould growth. Once black mould forms, it can cause health problems, such as breathing issues and skin irritation. Such conditions can be particularly dangerous for children and the elderly.
Luckily, there are lots of different ways to tackle condensation. We’ll explore these below.
What is condensation?
There is water in the air all around us. However, we can’t see it because it’s in the form of a gas (water vapour). When water vapour hits a cold surface, it turns into water droplets. This is known as condensation.
A common place to spot condensation is on the inside of your windows. Firstly, water vapour in the air hits the cold surface of the glass. Next, the water vapour starts to condense (turn into) water droplets. Finally, you’ll see water droplets on the glass.
What are the signs of a condensation problem?
A little bit of condensation is inevitable, and not something to worry about. However, if a lot of moisture builds up in your home, then you might find:
- Black mould
- Wallpaper starts to peel and rot
- Mould on furniture and clothes
- A musty smell develops
How to get rid of condensation mould
Condensation needs two things. Firstly, there has to be excess moisture in the air. Secondly, there must be cold surfaces which the moisture can condense on. If we can reduce one (or both) of these, then we can keep our homes healthier.
Reducing moisture in the air
To reduce the amount of moisture in our homes, we can either:
- Release less moisture into the air
- Give the moisture a way out of our home.
Through breathing and sweating, one adult creates almost a litre of water vapour every day. That’s before we even think about the water vapour that comes from cooking, washing our clothes, or washing ourselves. Eventually, all that water vapour has to go somewhere. If it stays in the home, then it’ll likely end up as condensation.
There are a couple of different ways we can release less moisture into our homes:
This reduces the amount of steam that’s released into our kitchen. It’s also great for saving energy because keeping the heat in the pan will cook the food faster.
As wet clothes dry out, that water evaporates into the air inside our homes. Where possible, dry your clothes on a line outside.
Some activities –– like showering –– can’t be done without producing a lot of moisture. In these cases, we need to move that extra moisture somewhere else before it becomes condensation. Ideally, we’d like the extra moisture to move outside. This is where ventilation comes in.
Ventilation simply means letting air flow between the inside and outside of our homes. As a result, our homes stay fresh and healthy.
You can ventilate your home and reduce condensation by:
This is especially helpful for avoiding condensation in kitchens and bathrooms. When cooking, open a window if you can. After showering or bathing, it’s also good to leave a window open if you can. Bedrooms are another important room to air regularly. This is because a third of our lives are spent sleeping, during which time we create a lot of moisture.
Again, these are most useful in the kitchen and bathroom. The fan draws moist air from the room and sends it outside.
Whether you’re cooking or washing, keep the door closed. Otherwise, that moist air will move to other parts of your home. Then, when you’ve finished cooking or washing, simply open a window or turn on the extractor fan.
Leaving a slight gap between furniture and a wall helps airflow.
Your windows might have “trickle vents”. They’re usually found at the top of the window, on the underside of the frame. A small lever lets you open and close the vent. If you have trickle vents, then leave them open for better ventilation.
Your walls might have vents or air bricks to help with ventilation. Air bricks are bricks with a pattern of holes in them. They look a bit like a waffle.
If you have vents or air bricks, then make sure not to block or cover them.
Reducing cold surfaces
Water vapour turns into water droplets when it hits a cold surface, so keeping surfaces warm is another way to stop condensation.
Keeping all rooms above 15 degrees should stop condensation forming. If you have thermostatic radiator valves (TRVs) then try setting these to 2. If you have Smart TRVs then simply set the temperature to 15 degrees.
If your home is draughty, this can create cold surfaces. Draughts also allow moisture to move from one room to another. To help tackle draughts, we’ve put together a handy draught proofing guide.
- Only draught proof kitchen and bathroom windows if those rooms have extractor fans or trickle vents
- Draught proofing the internal kitchen and bathroom doors should stop moisture moving to the rest of your home. However, make sure you:
- Talk to a draught proofing professional before draught proofing a room with a boiler, cooker, gas or solid fuel heater
- Don’t draught proof a room if it already has a condensation problem
The number one action we can take to make our homes warmer is to insulate them. Since it’s so important, we’ve dedicated a whole section of our website to insulation. There, you’ll find advice on everything from loft to wall insulation.