Brick cleaner, black spots
- Thread starter bm_999
- Start date
No idea, just daw them after jet washing the drive
Any from.amazon or similar?
I am starting to sound like a sales person for BAC (Benzalkonium Chloride) given my other posts!
However its more effective and longer lasting than bleach (sodium hypochlorite) although it takes a couple of months to be fully effective. This is same chemical Patio magic and Wet and Forget products use but less than a fifth of the cost!
However its more effective and longer lasting than bleach (sodium hypochlorite) although it takes a couple of months to be fully effective. This is same chemical Patio magic and Wet and Forget products use but less than a fifth of the cost!
Soldato
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You can usually only get it from a local building store, becuase these days it's outlawed for the general public. It's basically concentrated sulphuric acid.
The problem with such acidic prodcuts is they fade the colour of the material they are applied to and damage the material. If you’re trying to remove organic discolouration then a biocide is the way to go.
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They use it for quick effect despite poor longevity and ignoring damage to surfaces. I started down this road many years ago with companies that would only use ‘hypo’ and realised the compromise so now use a couple of biocides for best results, no damage and best longevity.
My roof, patio, block paving and even fence panels show the benefit of a targeted treatment so I will stick with that.
Could you send me a link to the products you use for this please?
Just google BAC50, its available from chemical suppliers on Amazon, eBay or direct from the same suppliers. Where is best depends on delivery for the quantity you want.
DDAC is also an option but BAC is more commonly available.
Edit: For general use BAC at 2% is a good mix to dilute to for use. For ref: Patio Magic at 1:4 to water is 1.8%, Wet and Forget diluted is about 1.7% BAC
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Cheers. I've been using some sodium hypochlorite and it does a decent enough job but I don't want to damage the patio and it's not a really long term solution. I'll give the BAC a try.
Just don't be put off by the very slow action unlike hypo. It will work in the end.
The bricks look great after using the acid. If used correctly it doesn't damage the bricks...
Brick acid is an effective cleaner, but it can damage brickwork if it's not used correctly. The hydrochloric acid breaks down the minerals in bricks and converts them into salts. This neutralisation reaction can weaken the brickwork and make it brittle. To prevent this, always wash away residual acid with water and never soak bricks in acid-based cleaners for prolonged periods. Brick acid shouldn't be used on natural stone surfaces like marble.
Source: https://www.chemicals.co.uk/blog/do...is an effective,brickwork and make it brittle.
Having to wash away the acid is one reason why why biocides are better for organic staining as you don’t rinse them off. I use biocides on my drive, patio, roof, fence, painted garden furniture etc and acid is not suitable for all these.
I tested hypo on a spare bit of my roofing felt and it damaged it, whereas BAC didn’t do anything even at 5 times over normal usage strength.
No I wouldn’t use brick acid on roofing felt but for badly marked bricks it’s fine if used correctly. As context is key I would not use “better” as it depends on users situation.
So in what context is hypo better than a biocide for organic staining?
Speed is the only advantage I can think of but that's at the cost of longevity, not being effective for all types of organic staining and potential damage to other surfaces due to over spray.
You are on a mission. I’ll leave you to it thanks.