That chalky white film is not dirt sitting on your pavers, it is mineral salt that has travelled up through the concrete and been left behind as water evaporated off the surface. Which is why washing it does very little: you are trying to clean something that is coming out of the stone rather than sitting on it.
Concrete contains soluble salts. Water moving through a paver dissolves them, carries them to the surface and evaporates, leaving the salt behind as a white crystalline film.
Because it is being delivered from inside the unit, cleaning the surface only removes what has already arrived, and more turns up on the next wet and dry cycle. On new interlock this is normal and usually clears within the first year or two as the available salt is used up.
On older surfaces it means water is moving through the pavers or the base in a way it was not before, so the useful thing to check is drainage rather than cleaning frequency.
Treatment is a cleaner formulated to dissolve the deposit, used carefully because most are acidic and the wrong strength will etch the face. See how paver sealing interacts with it, what pooling water does underneath, and why pressure washing is not the answer here.
Efflorescence
How It Runs
Four steps to a surface without the white film
Confirm it is efflorescence
A white film can also be sealer haze or cured polymeric binder, and those need completely different treatment. Getting it wrong is expensive.
Test the cleaner somewhere hidden
Most efflorescence products are acidic. A test patch out of sight shows how the surface reacts before the whole area is committed.
Treat, dwell and neutralise
The product is applied, given time to dissolve the deposit, then rinsed and neutralised so nothing is left working on the paver.
Look at where the water is
If it keeps returning on an older surface, something has changed underneath, and that is a drainage conversation rather than a cleaning one.
Seal Or Wait
Sealing over efflorescence traps it
Sealer is a film, and a film over a surface that is still pushing salt outward traps that salt underneath it where it shows as a permanent cloudy patch. On new interlock the sensible move is to wait out the first season or two, treat what appears, and seal after that.
We will tell you to wait rather than take the sealing job. See what sealer stripping costs if that advice is skipped, how paver sealing is sequenced properly, and what pooling water keeps feeding through the paver.
Mineral salt from inside the concrete, carried to the surface by water and left behind as it evaporated. It is normal on new interlock and usually clears within a year or two.
Only what has already reached the surface. More arrives on the next wet and dry cycle, because it is coming out of the paver rather than sitting on top of it.
Because water is now moving through the pavers or the base in a way it was not before. On an established surface that is a drainage question worth asking.
You can, and it traps the salt under the film as a permanent cloudy patch. Better to treat it, wait out the first season or two on new work, and seal after.
Not structurally. It is a surface appearance issue. What matters is the water movement causing it, which can be doing other things underneath.
On a new surface usually, because the free salts wash out over the first year or two. On an old one it will not, because something is feeding water through the paver and that has to be found. We look for the water before we touch the bloom.
White haze on the new pavers had me thinking they were ruined. They cleaned it with the right product, rinsed properly, and the colour came back fully.
Jill N.
Markham
★★★★★
Two other companies wanted to seal over the efflorescence. This crew explained it would trap it, cleaned first, and sealed a month later.
Emma V.
Toronto
★★★★
They tested a small patch before treating the whole driveway so I could see the result. No guesswork, no bleached spots.
Ken Q.
Richmond Hill
★★★★★
The salts came back once after the first cleaning, as they said they might. They returned and did the second pass at no charge.
