Salt bloom does not go away on its own. And it is not the problem.

What you see

White, sometimes fluffy efflorescence on brick, plaster or paint, coming back after every clean. Paint blisters and flakes around it. The plaster turns crumbly, sounds hollow, falls off in sheets. Often low on a wall, in a cellar, or on a façade facing the rain.

Some of these salts are hygroscopic: they pull moisture from the air. A wall loaded with them stays damp to the touch even once the water has stopped rising.

Where it comes from

From water passing through the masonry. Rising damp is the most frequent cause: ground water carries nitrates and sulphates, it rises, it evaporates, the salts stay. Water coming in through a buried wall or a façade does the same. The salt is the symptom, the water is the cause.

What we do

The cause first: injection, waterproofing, repointing, whatever the readings show.

Then desalting: strip the contaminated plaster to 50 cm above the marks, dry-brush the brick, and depending on the salt load, poultices or a renovation render that traps the remaining salts without bringing them to the surface.

Then the finish, after drying: vapour-permeable render and paint. A waterproof paint applied too early blisters within months.

What it costs

Desalting and renovation render are priced per m², on the Belgian market generally between 40 and 80 € per m², on top of treating the cause. Indicative range; the quote is put in writing after the visit.