I laid a patio last week and did a reasonable job of clearing up after myself for the most part but the last bit of pointing up was at the end of the day on a Sunday and I was back at work on Monday and we had a few wet days. Fast forward (via a busy week and being distracted elsewhere) to this weekend and the stains are a bugger to remove – I tried a wire brush but it was marking the slate. I have some Everbuild 407 Mortar stain remover but I don’t think I should use that as the patio backs straight onto my lawn and it’ll kill the grass.

So the question is – what is the best way of cleaning it up that doesn’t involve strong chemicals? I don’t want to attack the pointing with my jet wash just yet!

I would just use a wee drop of your acid based liquid as it froths away eating up the mortar, you will be flooding it with water to rinse and some plants like a wee bit of acid or sprinkle a dusting of lime to balance it

Brick acid will do it. Plenty of water to dilute it afterwards. Shouldn’t effect the grass at all. Brush it on with stiff broom or scrubbing brush. Wear proper rubber gloves (builders ones, not marigolds) and some safety specs or goggles. Have a bucket of water on hand just in case.

When you say ‘brick acid’ I assume you mean the same stuff as I have? I do have proper acid proof workboots, heavy duty gloves and safety goggles. Should I use a face mask too (as advised on the packaging but I don’t currently have) or would I be okay without?

Should I use a face mask too

Well ventilated area should be fine especially with a bit of a breeze blowing through. Breathing the various gases given off during such a reaction is not ideal for your lungs.. also don’t spray it all over your trousers during application…makes a bit of a mess of dye.

Anyway, I know what I am doing when it comes to safety wear – me kitted up for dealing with a wasps’ nest 🙂

Make sure you do your rams before you start, i admit i use it occasionally to clean tools or to give an aged look on certain things and dont wear gloves until it nips a wee bit then douse the hand in water, i would use it neat as its useless watered down.
Not as strong as it used to be

Not as strong as it used to be

Apparently the one I have is stronger than the normal stuff though. (18% IIRC).

Don’t use it all though. The brick acid makes good deruster.