Cleaning bricks - white vinegar, sugar soap?

[Spoilt Victorian Child]

I've got an exposed brick wall that had lime plaster on it. Most of the lime plaster came off in clean chunks, but the bricks are still looking a little 'dusty', and have a powdery white look about them, which I guess is still the lime residue. I washed them with water but once dry the hazy white appearence returned.

Was thinking of cleaning them gently with white vinegar, it's acidity hopefully will clean the alkaline lime - but wonder should I water it down? And should I wash it off afterwards? Will it eat into the brick?

Would sugar soap work better? I don't actually know what it is! I just know it cleans certain things brilliantly, and I'm looking for something gentle.

 

[plasticpigeon]

Even a strong acid won't damage the bricks, although it will eat away the mortar a bit. Yes try vinegar, but you may end up using a stronger acid like a diluted brik acid as i think that wine vinegar may not be strong enough to react with all the lime on the surface.

 

[Spoilt Victorian Child]

I'm so clumsy I'm just dead scared of using proper brick acid - it' not just the bricks I'm trying to protect it's me!

 

[Flyfisher]

I agree with PP that vinegar may not be strong enough and that brick acid would probably be better. I wouldn't panic too much about the term 'acid'. Brick acid is quite a dilute acid (10 - 15% hydrochloric acid I believe) and is not going to burn through everything it touches 'Alien style'. :wink:

That said, it needs to be treated with due care and attention but basic overalls/old clothes leaving no exposed skin, some heavy duty rubber gloves and suitable eye protection is all that's really needed.

Try to use it only on the actual bricks if possible to avoid it affecting any lime mortar.

 

[chuckey]

Soak the bricks with a hose first otherwise the acid will soak into their interior, never to be seen again. Don't worry about harming the lime you will run out of vinegar and time before the body of the pointing is attacked. Using acid dissolves out the lime, leaving a matrix of sand particles barely hanging on, so a good stiff brush up to remove them, then some more vinegar to loosen some more. Unless you are doing a very small area, I would use brick cleaner with its hydrochloric acid. It not that bad, a splash of the neat stuff, just brings up a red patch on my skin and it itches for a bit.
Frank