Cleaning roughcast

Bleach works very well on any surface,for outside, I dilute it 50 %. For interior rough surface I would try rubber gloves to hold a cleaning rag wet with 50 % bleach , it will take a couple minutes to work .

,Trade centers like B&Q, Wikes, Jewson, Maningham concrete and others have mortar cleaning solution Muriatic acid made from hydrochloric acid-water and other trace minerals. It cleans even old dry cement and other familiar adhesives, tile adhesives and grouts.

sometimes you have to watch it to be able to answer this question

Well i would do with wire brush or power wash

There is a liquid called Mortar cleaner.

Brick acid.would be the best solution

try removing as much of the cement as u can and soak area with either brick cleaner acidic cleaner let soak in then high powered jet wash and wire brush hope this helps

Try to remove the cement stains or mortar residue with one part vinegar and one part warm water. Then you brush this solution onto the surface. Leave to absorb and then rinse with clean water. Depending on the type of surface, you can remove cement stains and mortar stains with sandpaper or a scraper.

Hi there
If this is brick or stone you could try acid cleaner for bricks or just use a power washer

A cleaning solution for mortar should be able to sort that for you

You need to find where the water riseing because it won't go

Diluted brick acid

Hi I would test a small area with brick cleaner then warm soapy water to clean it down

Brick acid, water and jet wash should do the trick

Mortar stains can be removed by a jet wash and a stiff brush. But if the mortar stain is ingrained into the surface of the stone paving then a paving specialist will need to remove it

Diluted acid wash

Try using a wire brush or pressure wash

Clean with a diluted brick acid cleaner or paint over

It's needs to be scrapped off using a scraper if it's on silicone render

U can try brick acid but it all depend on the surface witch the stain is on