Best time to clean bricks???

[Fr_303]

Did a brick retaining wall on the weekend when will be the best time to clean the bricks with acid?
Also what mix (acid to water) do you guys recommend?

[Brickie]

Give it a week then clean it, dont do it the next day..:rolleyes:

Owwhh, and look here (http://www.brickwork.net.au/Acid_Washing.html)

[Fr_303]

Give it a week then clean it, dont do it the next day..:rolleyes:

Owwhh, and look here (http://www.brickwork.net.au/Acid_Washing.html)

Thanks that site was helpful. One question i have concrete under the wall that has been sealed. I will try as much as i can not to get the acid on it but if it does can it cause damage??

[Brickie]

The acid will take the surface off the concrete its the what acid does best.

Maybe you can flood the area with water? This may stop the acid from reacting, no guarantees though.

[Fr_303]

Thanks flooding the floor was what i was thinking of tring it should be ok.

[Brickie]

The acid neutralises with moisture, you will still get some reaction though.:)

[Cementer]

Thanks that site was helpful. One question i have concrete under the wall that has been sealed. I will try as much as i can not to get the acid on it but if it does can it cause damage??

The concrete you say is sealed, I take it the concrete is stenciled or something cosmetic like that. If so, the sealer will be resistant to acid in such a way the acid should not affect it too much, but still flood it for extra safety.

[MrFixIt]

Hi

The acid neutralises with moisture, you will still get some reaction though.:)

Hydrochloric acid is NOT neutralised with water, if it was, then the act of putting the acid in the water to dilute the acid, would aslo nullify the ability for the acid to clean the bricks.

The acidity is weakened by the dilution of the water but the acidity still remains.

There is a product that can be used to neutralise the acid effect, but I don't recall the product name and Bunnings were no help either :)

Flooding the concrete area below the bricks, while cleaning will help, but be aware that the acid action though a very weakened solution, will still be in effect. If the flooding water "pools" in an area on the concrete (or similar) surface it may possible cause a "stain" or "patch" just be sure to substantially flood the area and hose down the area afterwards to clear any potential "pooled" water areas.

[Brickie]

Hi


Hydrochloric acid is NOT neutralised with water, if it was, then the act of putting the acid in the water to dilute the acid, would aslo nullify the ability for the acid to clean the bricks.

.

Good pick up..

Maybe I should have said become weaker the more diluted with water it becomes?

[autogenous]

24 hours

Mix acid max 10 water 1 acid. NO MORE :)

Wet wall, brush on acid mix, scrub with an extremely stiff brush like hell and remove any dags with a steel spatula.

Once you think you have a desired result wash thoroughly with more water.

Neutralise the acid solution with 15 grams of washing soda per litre of water.

If you mix the acid beyond recommended then you will burn the wall or produce vanadium stains.

Do not treat efflorescence with Hydrochloric acid. HA compounds the problem..

The only way to remove Efflorescence is with a stainless wire brush. Any water will bring more Efflorescence to the surface.:oo: