Can a dehumidifier dry out damp walls? It can, but only if you choose the right one

Will a dehumidifier dry out damp walls? Here’s how to avoid mould growth and structural damage with this little helper

A Meaco dehumidifier by the side of a sofa in a living room with dark walls
(Image credit: Future PLC/Holly Jolliffe)

Seriously, is there something that a dehumidifier can’t do? These multifunctional appliances rise to many an occasion. But will a dehumidifier dry out damp walls?

It’s no secret that we love our dehumidifiers around here. But let’s face it - buying one is quite the investment as most of the best dehumidifiers are not exactly cheap. So, of course, we want to get our money’s worth. And since we’ve learnt that dehumidifiers do indeed dry clothes, we wondered if it could also be how to deal with damp.

And we were very happy indeed when we learned that a dehumidifier will help in drying out damp walls. As long as you get the right kind and follow a few easy, expert-approved guidelines. Here’s all you need to know.

Will a dehumidifier dry out damp walls?

A Meaco dehumidifier by the side of a sofa in a living room with dark walls

(Image credit: Future / Heather Young)

With their genius ability to extract moisture from the air, we always wonder what more a dehumidifier can do - does it get rid of mould? And will it dry out damp walls?

While it is more of a preventative measure in the case of mould, a dehumidifier is indeed an expert-recommended tool for getting rid of damp in the walls.

‘A dehumidifier can effectively dry out damp walls,’ says David Miloshev, Fantastic Services' HVAC expert and appliance technician. ‘Experts often recommend using this appliance in cases of dampness to prevent mould growth and structural damage and maintain a healthy indoor environment.’

However, a dehumidifier won’t necessarily stop dampness coming through the walls single-handedly as it only treats the symptoms of the issue. The root cause must be addressed, ideally before you even bring the dehumidifier in.

David Miloshev
David Miloshev

David Miloshev has worked with Fantastic Services as an appliance technician and certified electrician for more than 5 years now. In an environment where malfunctioning household appliances can disrupt simple daily routines, he quickly stood out during his training with a profound understanding of the technology that keeps his clients' homes running smoothly. This comprehensive training equipped him with the skills and knowledge needed to diagnose and fix a wide array of appliance issues and he quickly became an irreplaceable asset to Fantastic Services' team.

‘The root cause of the damp walls must be addressed or the problem will continue regardless of having a dehumidifier in the room,’ warns Thomas Goodman, property and construction expert at, the UK’s leading trades matching site.

‘Damp specialists usually recommend treating the cause of the damp before installing a dehumidifier. To address the cause, you’ll need to do some investigation into the possible reasons or hire someone to carry out a damp survey on your property. Damp walls can be caused by a variety of things including flood damage, leaking pipes, rising damp, penetrating damp and condensation.’

A living room with a colourful painted stripe

(Image credit: Future PLC/Joanna Henderson)

Best dehumidifiers for damp walls

While dehumidifiers are very effective at drying out damp walls, it is very important to choose the right one - from the right size to the right kind of dehumidifier.

‘When choosing a dehumidifier, it’s important to pick the right size for the area of the room. A small dehumidifier will not be very effective in a large room,’ Thomas advises.

David continues, ‘For drying damp walls, a high-capacity mechanical dehumidifier is what’s often recommended. These units are effective in removing large amounts of moisture from the air by drawing damp air over a refrigerated coil with a fan and this cold evaporator coil condenses the water. It’s also recommended to look for a dehumidifier with a built-in humidistat to control the indoor humidity levels.’

The best dehumidifier for damp walls we’ve come across is the EcoAir DD1 Simple MK3 Dehumidifier which we’ve previously reviewed. But these will also do the job:


How long does a dehumidifier take to dry a damp wall?

‘The time it will take for a dehumidifier to dry out damp walls will depend on a few key factors such as the extent of the dampness, the size of the area and the dehumidifier's capacity,’ David says. ‘In general, this can be several days to a few weeks to achieve significant results and regular monitoring of the indoor humidity levels and adjusting the dehumidifier settings will be necessary to help optimise the drying process.’

Virilis paint

(Image credit: Graham and Brown)

What is the best way to dry out damp walls?

A dehumidifier paired with optimal ventilation is a great way to drive damp out of your walls. Just follow a few easy tips.

‘You should ensure it is in the correct position in the room. Place it close to the damp area allowing enough space around it for air to circulate. When the wall begins to dry out you may notice the dampness receding leaving behind a “tide mark” on the wall,’ Thomas explains.

David adds, ‘However, besides that, you’ll also need to provide good ventilation and allow airflow by opening the windows and doors, which will help in expelling humid air and bringing in drier one from outside.’

We are continuously impressed by this small but mighty gadget! We’re off to look for more dehumidifier hacks now.

Sara Hesikova
News Writer

Sara Hesikova has been Ideal Home’s News Writer since July 2023, bringing the Ideal Home’s readership breaking news stories from the world of home and interiors. Graduating from London College of Fashion with a bachelor’s degree in fashion journalism in 2016, she got her start in niche fashion and lifestyle magazines like Glass and Alvar as a writer and editor before making the leap into interiors. She feels the two are intrinsically connected - if someone puts an effort into what they wear, they most likely also care about what they surround themselves with.