What is the best time of day to use a dehumidifier for reducing damp?

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Dehumidifiers can be extremely useful when used to extract excess moisture in the air. They are a very effective way of reducing condensation and damp. And can be great when you are trying to dry an area out.

So, what is the best time to use a dehumidifier?

When will you get the best results?

And when will it be the most cost effective?

The best time to use your dehumidifier is not set in stone. It will depend largely on the circumstances it is being used in.

Ideally, you should use it as soon as excess moisture is present in the air. By extracting moisture, you will avoid condensation forming on surfaces. As a result, this will help you to avoid damp in your home

Below are a few examples of the most efficient times to use your dehumidifier.

Best time of day to use a dehumidifier for cost

If price is your primary concern, then you are best using your dehumidifier outside of peak hours, if this is an option.

In general, the cost per hour of your dehumidifier will vary based on the model. This can range considerably based on the size and power consumption of the specific dehumidifier.

However, all dehumidifiers will be cheaper if you have the option to use them off peak. The main question at this point, is do you have an electricity tariff that benefits from variable rates, that are based on the time of day?

This is not the case for all electricity contracts in the UK. Many tariffs will not give you any discount based on the time you are using electricity. In this case, you will pay the standard kw/hour, whatever time you use your dehumidifier. According to British Gas, the standard rate in the UK is approximately 15p per hour.

If you are using a variable rate, you may be rewarded for using electricity at night. This is because wholesale electric prices are cheaper at these times, due to lower demand.

A variable tariff could see you paying as low as 5p off peak. However, the flip side might be paying 25p or more during peak hours. So, you could potentially save a good amount of money. But only if you use more of your daily consumption during off peak hours.

Off peak hours will usually range somewhere between 11pm and 6am. This can vary slightly based on the supplier, but these times are a good average example.

Best time to reduce moisture from daily tasks

If the main goal of your dehumidifier is to reduce moisture from daily tasks, then this should influence when you use it.

For example, rather than running constantly, you may want to turn it on at specific times. Such as:

  • During and after a shower
  • Whilst cooking, especially if this involves boiling water.
  • When drying clothes indoors. Obviously where possible you should do this outside.

These tasks will all produce excess moisture, and your dehumidifier can be a great way to extract this. However, it does not make sense to run it constantly for these reasons. You can simply turn the dehumidifier on as needed.

For removing moisture when drying clothes, you may need to run the dehumidifier for longer periods.

A good idea is to isolate this activity to a single, smaller room, with the door closed. This will allow your dehumidifier to work more efficiently, as it only needs to extract moisture from a small space.

You can also combine this process with your central heating. By heating the room, your clothes should dry faster and there will be more moisture in the air. This will mean more moisture passes through your dehumidifier, allowing it to condense and collect faster.

One thing to consider here, is the speed your dehumidifier fills. You should make sure to empty your dehumidifier regularly when performing tasks like drying clothes. If it stops working because it is full, moisture will settle and cause condensation on other surfaces. As a result, this could cause damp issues.

Best time to use a dehumidifier when drying a room

Another time you may want to use a dehumidifier, is when you are drying damp or wet areas in a room. This could be for many different reasons. You can see a few good examples below:

  • Extracting moisture after you wash your carpets
  • Drying a room after fresh plaster has been applied.
  • Drying up existing damp issues

For any of the above mentioned tasks, it is usually recommended to run the dehumidifier until the moisture is gone. It is unlikely that there will be any specific “best time”. Realistically you should start removing moisture from the air as soon as possible.

Therefore, you should start the dehumidifier as soon as the work is completed. Then you can leave it running until the area is dry and all moisture has been removed.

Again, all the above can be combined with central heating to help speed up the process. You should also keep an eye on the dehumidifier. Your goal should be to empty regularly, to avoid it completely filling and cutting out.

For the last example (drying damp with your dehumidifier) you should always make sure the cause of damp has been fixed. This should always be done prior to using the dehumidifier. There is no point in trying to extract moisture if the damp is continuing to enter.

You should identify the root cause and fix this first. Once the cause of damp is fixed, your dehumidifier can be an excellent way to aid in the drying process.


In conclusion, there are many different instances where a dehumidifier can be used. This means, the best time of day to use a dehumidifier, will vary depending on the exact issue you are trying to address.

In some cases, you may only need to use it at specific times of the day, for short periods. In other cases, you may need to use it for an extended period.

It is also worth considering the cost. If you are on a variable energy rate the best time to use your dehumidifier might be the night, as this could save you money.