The basement is one of the most damp-prone areas of the home. It is often situated wholly or partly below ground level, is cooler than the rest of the house and can be affected by both ground damp and humid outdoor air. That is why high humidity in the basement is a common problem, particularly during the summer. A dehumidifier can help maintain humidity at a suitable level and create a drier environment. However, not all dehumidifiers are suitable for the conditions found in a basement.
A basement dehumidifier needs to be able to cope with larger areas, high moisture loads and lower temperatures. That is why the combination of high dehumidification capacity and high airflow is important. The dehumidifier needs to be able to both remove sufficient moisture and circulate large volumes of air throughout the space. For consistent humidity control, the dehumidifier should also have a built-in hygrostat that automatically regulates operation according to the set humidity level. As a basement dehumidifier may need to be used for long periods, a robust design suited to prolonged operation is also important.
Basement walls and floors are often in contact with or close to the surrounding ground. At the same time, the temperature is usually lower than in the rest of the house. This creates the conditions for high humidity in the cellar.
The problem can become particularly apparent during the summer. When warm, humid outdoor air enters a cool cellar, the air cools down. This causes the relative humidity to rise, and condensation can form on surfaces that are cold enough.
This is why a basement can actually experience greater problems with damp on hot summer days, even though the weather outside feels dry and pleasant.
If the humidity is too high for prolonged periods, it can create an environment where musty odours, condensation and mould are more likely to occur. In the long term, the damp can also affect building materials and items stored in the basement.
The typical ‘basement smell’ is not something you need to put up with simply because your house has a basement.
A musty or earthy smell can be a sign of a damp environment where microbial growth has been able to develop in, for example, wood, cardboard, textiles or other organic materials.
If the basement smells musty, you see condensation or spot dark patches, a good first step is to measure the humidity with a hygrometer. Be sure to take readings in several places, as humidity levels can vary between different parts of the basement.
A common mistake is to look only at how many litres of water a dehumidifier can collect per day. That does not tell the whole story.
In a basement, dry air must be able to circulate throughout the entire space. If the airflow is too low, the air becomes dry only immediately around the dehumidifier, whilst moisture remains behind furniture, in corners, along external walls and in other parts of the basement. In a basement, it is important to choose a dehumidifier that combines high dehumidification capacity with high airflow.
If you look at the dehumidifier, it appears to be doing its job: the dehumidifier runs constantly and you empty the water tank. The moisture disappears from the air, doesn’t it? The machine is working flat out and, of course, it does collect water from the air, but it cannot cope with the whole space, so the relative humidity is still too high in large parts of the room.
This is why many people find that the musty smell and condensation persist even though the dehumidifier is running every day. The dehumidifier cannot cope with the harsh environment found in a basement.
The difference becomes clear if we compare two dehumidifiers designed for different types of spaces. Wood’s MRD14 is designed for bathrooms (smaller, heated spaces) and can remove up to 12 litres of moisture per day, with an airflow of 113 m³/h.
Wood’s smallest basement dehumidifier, the SW22FW, can remove up to 13.5 litres per day. The difference in maximum dehumidification capacity is therefore relatively small – but the air flow is 350 m³/h. This means that the basement dehumidifier can circulate just over three times as much air per hour.
In a basement, this is a significant difference. Damp air from, for example, corners, cold external walls and more remote parts of the basement needs to reach the dehumidifier, whilst the drier air needs to be able to circulate back throughout the space.
Put simply: the dehumidification capacity determines how much moisture the dehumidifier can remove, whilst the airflow helps it to treat the air throughout the entire basement.
A basement is a considerably more demanding environment than other parts of the house. To effectively reduce humidity, you need a dehumidifier that has:
A dehumidifier intended for use in a cellar must be more powerful and robust than one intended for a bathroom or living room, otherwise it will not be able to cope with the task.
See our range of basement dehumidifiers and compare models for different sizes and needs. All models in Wood’s SW series will solve damp problems in the cellar, but those with a higher capacity will remove the damp more quickly and will also be more energy-efficient in the long run, as they do not need to run for as long.
Dehumidifier for basements, garages and attics
Dehumidifiers for basements, garages and attics
Dehumidifiers for basements, garages and attics
Powerful dehumidifier for large basement and sanitation
In that case, you should buy a dehumidifier from the LD series. These are capable of removing all moisture from the entire basement, whilst also featuring a top vent that blows dry air onto your clothes. Your clothes will dry faster and you’ll have a dry, odour-free basement.
Dehumidifiers for drying laundry in basementsIf you recognise any of these problems, it may be a sign that your dehumidifier isn’t suitable for your basement:
Damp in the basement is common, as basements often combine cold surfaces, lower temperatures and proximity to the surrounding ground. A dehumidifier can help control humidity, but it is important to choose a model that is sized and designed for the environment.
Therefore, do not focus solely on how many litres of water the dehumidifier can remove per day. Dehumidification capacity, airflow and performance at lower temperatures need to work together.
With the right dehumidifier, you can keep humidity under control and reduce the risk of musty odours, condensation, mould and damp-related damage – throughout the basement, all year round.
This may be because the dehumidifier has too low a capacity or too low an airflow for the space. In a basement, it’s particularly important to choose a dehumidifier designed specifically for basement use. See our range of dehumidifiers for basements.
The most reliable way to check is to measure the humidity with a hygrometer. The fact that the dehumidifier is collecting water isn’t always a sign that the whole cellar is at the right humidity level.
Generally, a relative humidity of between 50–60% is recommended to reduce the risk of mould, odours and damp damage.
It depends on where the dehumidifier is located. In basements, crawl spaces and garages, we recommend running the dehumidifier all year round, but Wood’s dehumidifiers have a built-in hygrometer and will only operate when the humidity exceeds the set relative humidity level (around 50%).
Yes. Musty odours are often caused by high humidity. As the humidity decreases, the odour usually improves as well.
