How to clean Black Exhaust Staining from Pebbledash

[FrankDIYVirgin]

I live alongside a large highway and the pebbledash on my house has become grimy and black from the exhaust fumes of cars over the years.

I am desperate to find a chemical that will clean this black off the pebbledash.

I tried sugar soap, bleach, ammonia and soda crystals but none of it works.

Does anyone know what I can use?

Thanks

 

[joe-90]

Nothing is likely to work which is why masonry paint was invented.

 

[emilybronte]

Your only options as to paint it with masonry paint (and expect to have to renew it every 2 years), or pick off all the pebbledash and have it re-done ...but it will only get mucky again so I would go with masonry paint option.

If it were stone you could have it sandblasted, but it's quite a powerful process and it could wreck the render and bring half the pebbles off.