[Roland S]

hi

i cleaned a drive the other day and the customer asked if i could do anything with the wall which had thick efflorescence on it - it was hard and shiny like glass in places - i removed quite a bit of it with acid but the really thick hard bits need more dwell time with the acid, has anyone got any ideas?

[Smudger]

Grit blasting

[Roland S]

Grit blasting

yep that would do it, but i'm only really doing her a favourt by trying tp remove it so don't want to get too involved i was thinking of some sort of poultice, but thanks anyaway.

[Smudger]

effervescence can be a world of pain - certainly not one for doing "favours"

Darran

[Kev Martin]

Grit blasting

yep that would do it, but i'm only really doing her a favourt by trying tp remove it so don't want to get too involved i was thinking of some sort of poultice, but thanks anyaway.

Efflorescence when calcified is not easy to remove.  Poultice is useless unless you mix it with an acid and paste it in the area and cover it.  The easiest way is to use a diamond rasp in a Fein Machine as you have a lot of control.  Then use an acid to finish off the fine layer left.  But it is a tedious job and one you should be charging for properly.  The other thing to find out before you tackle any efflorescence problem is what caused it and has the cause been eradicated otherwise it will just come back.  Efflorescence requires 3 things to manifest itself ( Water, Salts and a Route) if you get rid of any one of them then efflorescence can't form. 

[Roland S]

Grit blasting

yep that would do it, but i'm only really doing her a favourt by trying tp remove it so don't want to get too involved i was thinking of some sort of poultice, but thanks anyaway.

Efflorescence when calcified is not easy to remove.  Poultice is useless unless you mix it with an acid and paste it in the area and cover it.  The easiest way is to use a diamond rasp in a Fein Machine as you have a lot of control.  Then use an acid to finish off the fine layer left.  But it is a tedious job and one you should be charging for properly.  The other thing to find out before you tackle any efflorescence problem is what caused it and has the cause been eradicated otherwise it will just come back.  Efflorescence requires 3 things to manifest itself ( Water, Salts and a Route) if you get rid of any one of them then efflorescence can't form.

thanks Kev, yes i thought it may be worth knowing for something in the future but sounds a right pain. i passed on a job cleaning an underpass last year for this very reason, and it was covered in it - the glassy efflorescence not the white dust - i would have still been there now.