Saltpetre, those annoying white patches that look like snowflakes on walls, is a common but solvable problem. In this guide, you’ll find out how to get rid of it, why it forms and how to prevent it from reappearing so your walls stay dry and beautiful.
Saltpetre is caused by moisture rising from the walls, carrying mineral salts with it. When the water evaporates, these salts settle on the surface, forming a white patina. This problem not only affects the appearance of walls, but can also compromise their structural health. To get rid of saltpetre, you need to take targeted action to eliminate it, understand the cause and protect your walls permanently. With the right solutions, you can say goodbye to this unsightly efflorescence and enjoy a healthy, dry home.
Why does saltpetre form and what causes it?
The main cause of saltpetre is rising damp. This phenomenon occurs when water from the ground is absorbed by porous masonry materials. During this process, soluble salts present in the soil or building materials are transported upwards. When the water reaches the surface and evaporates, the salts crystallize, forming these annoying efflorescences.
Other causes include
Poor-quality building materials: some materials contain salts that can migrate to the surface.
Insufficient waterproofing: the absence of a moisture barrier makes it easier for water to rise to the surface.
This problem is more common in older homes, but can also affect modern buildings if they are built without the necessary precautions. Treating saltpetre is not just a question of aesthetics: it’s essential to eliminate its causes to avoid more serious damage.
How to remove saltpetre from walls
To remove saltpetre from interior walls, simply follow these steps:
Remove surface deposits: use a stiff bristle brush to gently remove saltpetre. Don’t wet the wall, as this may aggravate the problem.
Cleaning with specific products: apply a chemical solution based on acetic acid or other specific products against salt efflorescence. Read the instructions carefully and use gloves and a mask to protect yourself.
Allow to dry thoroughly: it’s essential that the wall is completely dry before proceeding with any other operation.
Below you’ll find a video showing how to proceed and which products to use. Good vision.
These steps will remove visible saltpetre, but they won’t solve the problem at its root. To prevent recurrence, you need to act on the source of the moisture.
How to sanitize walls for the long term
To prevent the recurrence of saltpetre, it’s essential to eliminate rising damp and protect walls. Here are a few solutions:
Apply dehumidifying coatings: these products help evaporate residual water and prevent the formation of salts on the surface.
Create a chemical barrier: inject water-repellent products into walls to block rising water.
Restore watertightness: check exterior walls for cracks or defects and apply waterproofing materials.
By following these steps, you can permanently eliminate saltpetre and improve the comfort of your home. If the problem persists, consider calling in a professional for a targeted intervention.
