How to decorate damp or mould stained walls

Let’s get one thing out of the way, the first step before you even think of decorating a mould or damp stained wall is to diagnose and treat the problem. Mould and damp can affect your health so the problem needs to be treated as quickly as possible. Otherwise, no matter how good a job you do painting, the mould or damp will keep coming back and cause you problems.

Once you’ve identified and fixed the mould or damp problem it is time to get to work on preparing the surface ready for decorating.

Surface cleaners

There are a range of surface cleaners that are suitable for preparing a mould or damp stained surface prior to painting and these include anti-mould solutions, fungicidal washes and mould and mildew cleaners. Cleaning the surface will help to reduce any existing mould or damp staining and leave the surface clean and ready to prepare.

Surface preparation

As well as cleaning the surface you’ll also want to make sure that any dust or loose, flaky paint is removed using a stiff brush or scraper. Any rough edges will need to be lightly sanded down so that they are ready for priming. Any cracks or holes should also be filled at this point so that the surface is completely smooth and blemish free.


Once you have finished preparing the surface it’s time to prime it using a stain block or suitable primer. This will help to make sure that the stain doesn’t bleed through your paint and ruin the finished paint job. Zinsser is one of the best-known brands in the market and it offers a great choice of primers and stain blocks.


At this point, you can get to work on painting your walls with the colour of your choice. An extra step would include using an anti-damp treatment or stain block which will help to prevent future problems but this is not necessary. Prepare the rest of the walls to be painted in the same way as you would normally and if painting in areas of high humidity then it may be worth using a couple of coats of anti-mould paint.

Decorating a wall that has been damaged by mould or damp shouldn’t fill you with fear and is actually quite easy to get a good finish. Cleaning and preparing the surface properly means that the mould and damp will be a thing of the past.