Got one cold wall at home? This is what’s causing it and how to solve the problem before winter kicks in

With temperatures in single figures, it's safe to say autumn is well and truly here. But while it's cold outside, it's more important than ever that our homes do their job of keeping us warm.

Your home might be largely well insulated, but what does it mean if you spot that you have one wall at home that feels much colder than all the others? I asked the experts for the potential causes and the best solutions to solve the problem for good.

What might cause one wall in a home to be colder than the others?

There are a few reasons you might have one wall seemingly colder than the others in your home:

1. Wall positioning (especially if it's north facing and exposed rather than sheltered
2. Draughts around windows, skirting boards or sockets
3. Damp
4. Poor, compromised or missing insulation.

'The most common cause is that it is an external wall, especially one facing north or exposed to wind and rain, so it loses more heat than the walls inside the house,’ says Elliot Anderson-Evans, RICS Surveyor at Elliot & Hill, a Cardiff property firm. ‘After that, I would look at insulation. A wall can be missing insulation altogether, or have gaps in the cavity fill, which leaves cold patches.

'Damp is another big one. A damp wall feels colder because moisture draws heat out, so look for mould, staining, flaking paint or a musty smell.'

'Other causes are thermal bridging, where something solid like a concrete lintel carries cold through the wall, draughts around sockets and skirting boards, and a wall that backs onto an unheated space such as a garage or an empty neighbouring property. Furniture or a lack of radiator nearby can also make one wall feel colder than it really is.'

How can you solve the problem of a cold wall?

How best to solve the cold wall problem will depend on its cause, and identifying that cause isn't always easy.

At the easier end of the scale, if you can feel cold air around plug sockets or windows, then the issue is likely draughts which can be remedied quickly and inexpensively on a DIY basis. Similarly, a quick adjustment of your furniture placement to allow warm air to flow better around your room can help without costing a penny.

What should you do if the problem is damp?

However, if the cause is damp or an insulation issue, the solution may be more involved. 'The first thing would be to work out whether you're dealing with an insulation problem or damp, so check if the wall is just cold or whether you've also noticed peeling paint, damp patches or a musty smell,’ says Scott Godfrey, Construction Trade Consultant at Black Hammer.

It's crucial to get rid of damp before you address any insulation issues, otherwise you could end up trapping moisture and causing more significant damp problems, and ruining the lifespan of your insulation efforts.

The best solution will depend on the type of damp you have. If the damp is caused by condensation, then you need to address the excess moisture levels in your home and ensure you have adequate ventilation to help that moisture escape. Having one of the best dehumidifiers on hand can be worth it's weight in gold too.

For penetrating or rising damp, it can be harder to identify the root cause. Have a good look round to see if you can spot where moisture is entering. Once you've located that and stopped it, you can start to dry out and then repair the damage.

'It's also worth checking the condition of the outside wall, as really common things like damaged pointing, cracked render and leaking gutters can all allow rainwater to get into the masonry,' says Jack Reading from Emperor Paint. 'If moisture is contributing to the problem, any damage or sources of water getting in should be dealt with. One option is to apply a protective masonry paint or treatment.'

However you need to make sure you choose the right paint, and one that won't trap moisture and make damp problems worse. 'It's important to choose something breathable so moisture vapour can still escape from the wall rather than becoming trapped inside.'

What to do if poor insulation is making your wall cold

If you think the wall's insulation is the problem, then getting a professional assessment can be a wise move. 'If you are unsure what is going on, a surveyor or an insulation specialist can use a thermal imaging camera to show where the heat is escaping,' advises Elliot.

A professional assessment will also highlight the type of walls you have (if you are unsure) and what the best insulation options will be. It may be that you need to add or top up your cavity wall insulation, but if you have solid walls, you will have to insulate a cold wall from the inside, or opt for external wall insulation.

Cavity wall insulation is the most straightforward to install, where as internal wall insulation and external wall insulation can be a lot more complex.

It's best to seek the advice of a professional, and to make sure you avoid insulating areas you shouldn't, as this can trap moisture in your home, causing damp and mould.