The white salts that can build up on all forms of cementitious or clay bricks, slabs, tiles and blocks after they are laid can be very unsightly indeed. They often spoil an owner’s pleasure in a new house, wall, patio or driveway for months, or even years to come.
The cause is the entry of rainwater into the new masonry where it dissolves the various salts that originate from the very material used to manufacture the item. Over time the solution then finds its way to the surface where the water evaporates into the atmosphere leaving the salts behind.
Distressed owners of property affected in this way, asking for advice, will often be told to use water, preferably in a high pressure sprayer, to blast off the deposits. If not they may buy, at considerable expense, one of various proprietary mineral acid solutions recommended for the job of removing these surface salts.
These methods way well work – especially if the problem has only recently occurred and before it becomes entrenched and crystalline – BUT NOT FOR LONG!
Since the problem is one of liquid dissolving internal salts it can be readily understood that in applying more liquid the problem, in the long term, is simply made worse by these methods. It will keep recurring in a vicious cycle.
The only recommended way of removing the white or grey, powder or crystal salts is to physically rub them off, without re-wetting the surface, with a suitable brush.
Of course, this might make for a little more work as the whole area covered by the salt needs to be brushed, rather than sprayed. However, most efflorescence comes away without hard scrubbing by either a hand-held brush or handled broom.
In some light cases a domestic brush may suffice, but more difficult salts will need something stiffer to remove every vestige of white. A normal wire brush is not ideal. Made of iron it may be a little too aggressive and score the surface while, at the same time, leaving deposits that may appear as rust stains. The IDEAL SOLUTION is a brush with brass bristles. It won’t damage the surface or leave stains. One made for the purpose is WATER SHIELD’s Brass Bristle Brush.
Sometimes the salts will never reappear but, to be certain, we recommend the whole affected area is treated with liquid WATER SHIELD. It will allow the masonry to dry out without bringing the disfiguring salts to the surface ever again.
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