The 18C heating rule that could help stop mould growing in your home this winter

More than seven million households in England have problems with condensation, damp or mould - and those struggling to afford their heating are among the worst affected.

Government figures show that 58% of households unable to keep warm in winter reported damp problems, compared with 27% of households who could keep their homes warm.

With temperatures dropping and energy bills squeezing household budgets, many people will be tempted to turn the thermostat down.

But letting your home get too cold can make condensation worse, creating the conditions mould needs to grow.

The NHS recommends keeping the rooms you use most at 18C or above, if you can. This won't guarantee you avoid mould, but it can help keep your home at a healthier temperature.

And there are other ways to tackle damp without having your heating on full blast.

The 18C rule you need to know

The NHS advises that rooms you use regularly should ideally be kept at 18C or above during colder weather.

This is particularly important for older people and anyone with a health condition that makes them more vulnerable to the cold.

You don't necessarily need to heat every room to the same temperature. Focus on the spaces you spend the most time in, such as your living room and bedroom.

Try to keep the temperature reasonably steady rather than letting your home become very cold before switching the heating on.

If you have a thermostat, use it to help manage the temperature and avoid heating rooms unnecessarily.

Five ways to stop mould taking hold

Keeping your home warm is only part of the answer. Everyday habits can also make a difference.

1. Open your windows when you can

Cooking, showering and even breathing release moisture into the air.

Opening windows for a short time can help let damp air out, particularly after a shower or when cooking. If you have extractor fans, use them.

2. Use lids when cooking

Boiling pans without lids releases steam into your kitchen.

Putting lids on pans helps keep moisture in and can also reduce the amount of energy you use.

3. Dry clothes outside where possible

Drying wet washing indoors can add a lot of moisture to the air.

If you have to dry clothes inside, try to use one well-ventilated room and keep the door closed to stop damp air spreading around the house.

4. Wipe away condensation

Water collecting on windows and cold surfaces can encourage mould to grow.

Wipe it away when you spot it, especially in the morning, and try to keep the area around windows clear so air can circulate.

5. Leave space around furniture

Pushing furniture right up against cold external walls can restrict airflow.

Leaving a small gap can help air move around the room and reduce the chance of damp building up behind wardrobes, sofas and beds.

The tell-tale signs mould is growing

Mould doesn't always start with a large patch on the wall.

Look out for:

• Black, green or dark patches on walls, ceilings or around windows.
• A musty smell, even if you can't see where it's coming from.
• Peeling wallpaper or bubbling paint.
• Damp patches or condensation that keep coming back.

If you spot mould, don't simply paint over it. The underlying cause needs to be dealt with, otherwise it is likely to return.

Small patches may be manageable with an appropriate mould cleaner, following the product instructions. Wear gloves and avoid brushing or disturbing dry mould, as this can spread spores.

If the problem is widespread, keeps returning or is linked to a leak or structural issue, get professional advice.

Renting? Your landlord may need to step in

If you rent your home and are dealing with damp or mould, report it to your landlord or letting agent as soon as possible.

Explain where the problem is, when it started and whether it is getting worse. Taking photographs can also help you keep a record.

A landlord may need to investigate and fix problems such as leaks, faulty ventilation or structural defects.

In England, Awaab's Law came into force for social housing in October 2025. It sets time limits for social landlords to investigate and address serious damp and mould hazards.

If your landlord doesn't respond, you can seek advice from your local council or a housing advice service.

Struggling to pay your heating bills? Here's where to get help

Keeping your home warm can feel impossible when money is tight.

But if you're cutting back on heating because you can't afford your energy bills, it's worth checking whether you're entitled to extra support.

You may be able to get help through government schemes or other support available from your energy supplier.

Our free benefits calculator can show you whether you're missing out on financial support or benefits you could be entitled to.

And if you're struggling with household bills or other debts, speak to us. Our debt advice is free, and we can help you understand your options and find a way forward.

You shouldn't have to choose between keeping warm and keeping on top of your bills