Stains in concrete

[twobobsworth]

We recently had some stenciled concrete cleaned and resealed. After a fortnight a white milky stain appeared in a 3 x 1m section.

Any suggestion as to what has cause this? The tradie has so far not returned our calls.

 

[Spicy McHaggis]

it could be the new sealant reacting with moisture
do you know what he used?

 

[wylie]

Find another concrete finishing company and email the photo. They will have no reason to tell you anything other than the truth (if they know what this is caused by). Then you can go back to your installer knowing what the issue (probably) is and how the other company suggested it is fixed.

 

[Doovalacky]

Agree with the moisture comment above. Had same issue on my driveway in a low spot that had not dully dried out after I cleaned it.
Resealing it again hid it.

 

[twobobsworth]

Yep followed up again. It's moisture as you've suggested. They are coming out to fix.

 

[innerbath]

Firstly, would like to know what exactly you have used on the surface. But generally, its not really possible to scrub away oil, paint or grease stains on the concrete surface. The way to remove them is use some mixture like trisodium phosphate and water (an absorbent), once it absorbs the stain, just sweep it away.

This is just a suggestion, but my recommendation is to get in touch with a concrete finishing expert..

cheers
Josh