It is important that you remove any stains from your walls before painting, this is because if there are already watermarks present on the wall and you emulsion over it, the stain marks will return. The only way to resolve this is to use a water stain remover like Zinsser.

Stains on walls can be a breeding ground for bacteria, mould, and mildew. Regularly cleaning walls can help prevent the growth of these microorganisms and promote a healthier living environment.

Stains left untreated can become more difficult to remove over time. By addressing stains promptly, you can prevent them from becoming a larger problem and save yourself time and effort in the long run.

NOTE: When applying stain remover to your walls, use an old brush or a cheap one. This is because once it has been used the brush will become solid and unusable. 

You must stop the cause of the water penetration before applying the stain remover by:

- Maintaining the gutters and downspouts

- Framing and cladding the external wall

- Applying a liquid waterproof to external mortar joints

- Seal gaps and cracks 

- Prioritise waterproofing