Condensation running down a window

Do Damp Crystals Work?

28 November 2023

Discovering damp in your property is always going to be a problem, and there are plenty of people who won’t know where to start when it comes to dealing with the issue. In fact there are plenty of people who might rely on a home remedy rather than a professional, long lasting solution, based on information given to them from the people around them.

One of the home solutions suggested may well be the use of damp crystals, used within your property to absorb the damp being created and mitigate the issue.

Is this a viable solution though, and do damp crystals actually work? We are going to explore the usefulness and application of damp crystals in this article.

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What Are Damp Crystals?

Rising damp present on walls in house living room


Damp crystals are small, rock salt like crystals normally made out of calcium chloride, a substance known for attracting latent moisture present in the air. Normally, these crystals are contained in a plastic box, which usually contains two chambers, one on top of the other.

The top chamber of the box is where the damp crystals are situated, and where the moisture in the air is drawn to via the vents in the top of the plastic box. The chamber below is kept empty, so that the attracted moisture is able to slowly drip down and be collected safely.

The moisture collection chamber (the lower chamber) is designed in such a way that the moisture cannot escape, and therefore the collected moisture cannot present as damp or condensation in the room that the damp crystals have been used in.

The box that damp crystals are contained in are usually quite small, and are often suggested as an alternative to the use of a dehumidifier, as they are smaller and less expensive (especially taking into consideration the use of power in a dehumidifier, which damp crystals do not need).

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Are Damp Crystals Effective?

Evidence of condensation forming on interior window


The answer to this question depends heavily on the aim of the person using the damp absorbing crystals.

If, for example, you are looking to reduce the amount of moisture present in the air within your property within an area bereft of any ventilation, then damp crystals can be an effective tool at reducing the humidity level without being invasive.

However, if you are looking to damp crystals to solve a larger damp problem, then you may well be out of luck. Damp crystals are never going to help you eliminate a rising damp or penetrating damp problem, and are best used as a method to control humidity when ventilation is a problem.

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How Should Damp Crystals Be Used?

Closeup of condensation water droplets on a window


Damp crystals are best used as a method to control humidity in rooms where ventilation may be a problem, but not so much a problem that a dehumidifier or other forms of condensation control should be considered.

They are best used in smaller spaces, perhaps cupboards, utility rooms, or other such spaces that a dehumidifier might not be suitable for. Larger spaces are going to be too big for damp crystals to have any real effect, and its here that you should consider using a dehumidifier to control humidity levels to your preference, or explore condensation mitigation techniques.

You should also be aware that damp crystals do not remain perpetually effective. They will need replacing at some point, normally after being used for anywhere up to four months (depending on the moisture level present). This means that the cost of using damp crystals may not be as effective as someone might initially think, as the cost of replacing the crystals can stack up and compound over time.

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Are There Any Risks When Using Damp Crystals?

Black spot mould covering the interior walls of a property


The only real risk to health as far as damp crystals are concerned is the risk to children, and potentially pets, as the crystals could pose a choking hazard. Calcium chloride is a stable substance, a compound that will only serve as a moisture absorbing solution, without causing any other problems.

In fact, the argument could be made that the presence of damp crystals in your property is a benefit to your health, as the damp crystals could potentially alleviate the allergies worsening. This is because damp crystals, as they absorb the moisture in the air, reduce the chance of condensation building up on any surfaces in the area, in turn reducing the chance of black mould spores growing.

Black mould can be responsible for the exacerbation of several health issues, and anything that can be done to inhibit its spread in a property is always a welcome endeavour.

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Can Damp Crystals Stop Damp?

Black spot mould in bedroom in corner of ceiling

In short, no.

Damp crystals are best used as a form of mitigation against humidity in smaller areas, and they can prove effective in reducing the amount of condensation being created in these small areas, but they are never going to be able to put a stop to damp appearing in your walls, steamy windows after a shower, or rising damp ruining skirting boards.

In fact, for these problems, we recommend reading more on our website, and potentially engaging a damp proofing survey to help mitigate the damp problems you could be experiencing.

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Do Timberwise Recommend the Use of Damp Crystals?

Surveyor Checking Timber Beam In Loft

We would recommend the use of damp crystals in limited and specific situations. If you are looking to reduce the amount of humidity in a cupboard, wardrobe, or smaller room, then damp crystals can prove to be a useful tool at controlling moisture present in the area.

If you are looking to control the humidity in a larger space, like a whole room, then we recommend the use of a dehumidifier. Dehumidifiers are more effective at controlling the ambient moisture level in larger spaces, and might help you to achieve the same effect that damp crystals provide in a larger area.

However, for any other serious damp or condensation afflictions, we would recommend that you look into a professional solution. This might mean either reading more on the methods of controlling condensation further online, or booking a damp survey so that one of our highly experienced team can give you a full picture of the damp problem in your property.

You can read more about different damp problems online, or you can arrange for a damp survey with our team via the form below.