dehumidifer-on-window

Do Dehumidifiers Work Against Damp?

27 July 2020

Most properties at some point or another will have or will be affected by a damp or condensation issue. In this article, we propose the question: “do dehumidifiers work against damp?”.

Dehumidifiers are often perceived by many as a quick solution to getting rid of damp and mould however, this is not the case. It is in fact more of treating the symptom rather than employing a solution to get to the root cause of the damp problem.

There is no “quick fix” to treating damp in your property as there are a number of factors that need to be resolved to be able to rectify the damp problem effectively.

For example, if the damp problem has occurred on the outside of the property (for example due to damaged rainwater goods) then a dehumidifier is not the correct tool to use to rectify the problem.

Buying dehumidifiers may seem like the right option in the short term. Look at it another way – when treating a cold you would use a handkerchief; this would only help stop the symptoms of the cold, not get to the root cause of it.

There have been many instances where our surveyors have carried out a damp survey and the customer despite already having a dehumidifier in place still have damp problems. If dehumidifiers were effective at treating damp walls then why are they calling on a surveyor to assist them with their damp problem?

How Does a Dehumidifier Work?

A dehumidifier works by drawing in the moisture laden air to help reduce condensation and damp problems. There are two different types of dehumidifiers that are commonly used which work in different ways depending on what the temperature is in the property.

dehumidifier in bathroom

The two different types are called Refrigerant dehumidifier (compressor) and Desiccant dehumidifier (absorption):

Refrigerant (Compressor) Dehumidifiers

This type of dehumidifier pulls in the warm moisture laden air using a fan. The air is then filtered through onto the cold coils from which the water drips and collects into a water collection tank.

The water tank will need to be emptied regularly to ensure the dehumidifier is operating efficiently. The dehumidified air will pass through a hot compressor where it will heat up to a similar temperature to that was drawn in. This dehumidifier is best used when there are high temperatures in the property (e.g. bathrooms, living rooms and bedrooms).

Desiccant (absorption) dehumidifiers

This in comparison to the refrigerant dehumidifier uses absorbing materials to collect the water from the air. This dehumidifier then heats the absorbent material, so the water then drips into the tank.

Desiccant dehumidifiers are more effective in lower temperatures which are possibly not used on a day to day basis such as a basement or garage.

Do Dehumidifiers Stop Damp?

To put it simply the answer is no, however, if you are looking to reduce high humidity and the chance of condensation occurring then dehumidifiers can be a good solution. To get to the bottom of the problem it is important to understand why there are humidity levels in the first place.

Condensation occurs a result of people carrying out their daily activities such as cooking and drying their clothes inside. This where simple lifestyle changes can be made. Opening windows and doors where possible can provide clean, regulated air in and out of your property.

Open windows to reduce dampness

Other problems related to damp such as rising damp and penetrating damp are something that a dehumidifier cannot deal with.

Having structural defects at your property will need a professional to provide an inspection at the property and identify what remedial action needs to be taken to resolve the problem. Typical structural problems can be any of the following:

  • Having a damaged or indeed no damp proof course in place- if a property does not have an adequate damp proof course in place it can cause rising damp to occur as there will be no protection for water rising up from the ground.
  • Damaged rainwater goods- If your gutters are clogged or damaged then this will mean, especially during periods of heavy rainfall, that water will not drain away and could potentially penetrate through to the inner walls of the property.
  • Leaking pipes- If there are leaking pipes at the property then this will mean that has the potential for dampness to occur and should be rectified by a qualified plumber.

As you can see that there are many different causes of damp in houses and if the damp problem isn’t diagnosed or treated in a sufficient amount of time then the building could suffer from severe structural issues.

What Do We Advise on Dehumidifiers?

Dehumidifiers can be a “quick fix” to reducing high humidity levels in a property. However, if you are looking for a longer-term solution to getting rid of damp then it is best to stop the root cause of the problem.

Booking a survey with a qualified damp surveyor will provide you with expert advice on the root cause of the damp problem as well as detail the solutions to get rid of it. If you would like to speak to our team please contact us online or call 0800 288 8660.