Does damp proof paint work? Will it stop damp in your property?

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does damp proof paint work

In this article we will be looking at damp proof paint and answering the question, “does damp proof paint work?” Firstly, we will be looking at internal damp proof paint. This will be followed with a section on external damp proof paint.

Damp proof paint works because it contains a water-reactive agent. This takes care of residual surface moisture. As a result, the likelihood of damp occurring decreases.

It also contains a range of polymers. This means that damp proof paint is longer-lasting than conventional paint. For these reasons, many people turn to damp proof paint as a solution. After experiencing problems with damp in the home it seems a natural course of action. Damp proof paint is seen to be a good preventative measure to guard against the return of damp.

Yet, if you look online at reviews and forums, you’ll find a mixed bag of comments. Some people say it works well while others suggest that damp proof paint doesn’t work at all. So, does damp proof paint work? Damp proof paint is effective against surface moisture. But damp proof paint won’t help in all situations. For example, if it is a structural fault allowing water to penetrate the surface of a wall. It doesn’t stop all types of damp from occurring. It also needs to be applied correctly for it to be most effective.

How internal damp proof paint works

It’s the water-reactive agent in internal damp proof paint that makes it work. The paint makes sure that moisture doesn’t appear on the surface of the wall. It is not a treatment, in itself, for damp though. It works as a preventative measure that protects against damp re-emerging. You will need to fix any underlying issues that are causing the damp prior to applying a damp proof paint.

After the damp problem is treated, the next logical step is to apply damp proof paint to the wall. It covers up any damage that may have been visible. It also gives you that extra peace of mind and level of protection.

Damp proof paint has its water-reactive agent fighting the fight against damp resurfacing. Not only that, damp proof paint is also easy to maintain. It can be wiped down and reapplied at any time, once the original first coat is dry. This means you should years of service from the damp proof paint. You can rest assured that damp proof paint looks good. It compares with standard emulsions and matts.

When to use internal damp proof paint

Internal damp proof paint is suitable for many situations. But you must appreciate, it is a protective measure, it will not always treat the cause of the damp. It is vital that you deal with the cause of the damp problem. Damp proof paint is applied to a wall, afterwards.

If the house has had an issue with rising damp, a new DPC, or chemical DPC injection could treat the damp and fix the issue. Alternatively, if you have damp patches caused by penetrating damp. You will need to fix the defect allowing water to penetrate first.

Once the problem causing the damp is fixed you can apply the damp proof paint afterwards. This gives you a handy extra level of protection against the damp resurfacing.

Internal damp proof paint is great for adding a layer of protection. It is also a great way of covering up stains. These can be left after treating and removing black mould or damp patches. It’s important to note that damp proof paint only works against surface moisture. So, as we mentioned previously, if the damp on the walls is caused by structural defects, damp proof paint will not work on its own.

This is where the confusion comes from about the question of whether damp proof paint works or not. For example, you may have used damp proof paint as a way of dealing with excess moisture in your home. Further down the line, a property could suffer another type of damp. For instance, penetrating damp caused by structural defects. To all intents and purposes, it may look like the damp proof paint hasn’t worked. In fact, nothing could be further from the truth. You’ve had the misfortune to experience a different type of damp in the home. This is one that damp proof paint is powerless to prevent.

Avoiding poor application

It’s, vital that you apply damp proof paint correctly. Make sure you follow the manufacturer’s instructions. The surface you apply the paint to needs cleaning. It needs to be free from dirt and have any previous or existing coats of paints removed. You need a clean and bare surface. The water-reactive agent contained in damp proof paint will not be effective otherwise.

How external damp proof paint works

External damp proof paint works in a very similar way to internal damp proof paint. In that, it offers an extra level of protection. Applying a coat of damp proof paint to the external walls of a property can be an excellent preventative measure.

When to use external damp proof paint

External damp proof paint is a protective measure. Just like internal damp proof paint it will not perform miracles. For example, if a property is affected by penetrating damp, from poorly sealed windows and doors or damaged brickwork. External damp proof paint may not be effective on its own, to stop the problems you are seeing internally.

To get the best results from external damp proof paint, you need to treat the actual cause of the damp in a property. Before applying a coat of exterior damp proof paint, you will need to make sure you have fixed any other defects. These could be allowing damp to penetrate and may not be fixed by painting over.

Also, the surface you are painting needs to be clean of dirt and debris before painting. This will ensure the paint adheres well to the surface and provides the best finish.

All in all, damp proof paint on exterior walls is an excellent idea. External damp proof paint will provide years of waterproofing protection for your property.


Both internal and external damp proof paints do exactly what they say on the tin. They provide a useful layer of protection. A coat of damp proof paint reduces the risk of damp resurfacing. However, it comes with one, very important caveat. Damp proof paint is not a treatment that will fix every possible damp problem. In most instances, it is a prevention, not the cure.

Damp proof paint should be the icing on the cake. Deal with and treat whatever is causing the damp first and then damp proof paint can add additional protection.

Essentially you should only apply a coat of damp proof paint, after the main damp issue has been treated. Make sure the surface is clean and that you follow all product instructions to the letter.

In conclusion damp proof paint can work very well if used correctly. It provides a cost-effective extra level of protection against damp.