Yallah: 02 4257 2611
Bomaderry: 02 4423 5111
Batemans Bay: 02 4472 4944


Efflorescence in Concrete

Efflorescence is the formation of salt deposits, usually white, on or near the surface of concrete causing a change in appearance.

Apart from the discolouration, efflorescence is generally harmless. This is best described as being 'a skin trouble and not a deep-seated disease'.

Primary efflorescence is efflorescence occurring during hardening of the concrete.

Secondary efflorescence is the efflorescence resulting from the weathering of the hardened concrete.

Crypto-florescence is the deposition of salt within the pores of concrete below the exposed surface.

The force of crystallisation growth may cause some fretting.

Light coloured concrete shows the deposit much less than darker coloured concrete.

With time, efflorescence becomes less extensive. Efflorescence is most obvious in the winter, but may be observed throughout the year after a heavy rain and a drop in temperature.

Information Courtesy of CCAA

These pictures show the effects of efflorescence.
Efflorescence in Concrete EF-2Top EF-3Swepped-Area-Prior EF-4Applying-Hyd-Acid EF-5Just-After-Application EF-6Drying EF-8Drying-2 EF-11Water-Reapplied EF-12Water-Reapplied-1 EF-13Water-Drying-Again
Another classic example of efflorescence, this time with colour hardener

This concrete required 3 acid washes, with the concrete being wet down to avoid acid burning.

The acid was applied with enough acid added to the bucket of water to create a sizzle effect when applied to the concrete. A stiff bristled broom was used to vigorously scrub the concrete.

In the last picture, the concrete has not completely dried.

Treating Concrete Efflorescence - First Acid Wash EF_2First_Acid_Wash EF_3Second_Acid_Wash EF_4Second_Acid_Wash EF_5Third_Acid_Wash EF_6Third_Acid_Wash EF_7Nearly_Dry_Acid_Wash

Useful Links

YALLAH  [map]

70 Princes Highway
Yallah 2530
Ph: 4257 2611
Fax: 4257 2599

Yallah Supply Centre


1 McIntyre Way
Bomaderry 2541
Ph: 4423 5111
Fax: 4423 5105

Bomaderry Supply Centre


1 Russell Lane
Batemans Bay 2536
Ph: 4472 4944
Fax: 4472 4922

Batemans Bay Supply Centre


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