Green slime running down my pink pebble dash wall

[JamesEB]

My gutter leaked for a long time and left quite large green slime marks running down my pink pebble dash.

Would someone please tell me the best way to treat this.

Thanks
JamesEB

 

[endecotp]

scrubbing brush, or broom, and bucket of water.

 

[JamesEB]

Is that just clear water please?

Thanks

 

[endecotp]

see what happens.... maybe add a bit of detergent if you like.

 

[Nozzle]

Jayes fluid?

Nozzle

 

[Chri5]

Green slime, or do you mean it got so damp that moss spores have started to grow on the dashing?

 

[JamesEB]

Thanks.

It's thick green slime clinging on like a limpet.

There is no damage on the wall.

The wall isn't damp.

There could be moss spores growing there. There is moss growing on the floor.

JamesEB

 

[misterhelpful]

Apply a fungicidal wash or diluted bleach solution, allow to sit for a while, and then rinse. Several applications may be required as it's harder to clean this problem from pebbledash/spar.
If you have a pressure washer with bottle attachment, you can use that to apply your solution and then rinse with the washer set at it's widest setting, working at just the right distance away so as not knock off any of the dashing.

 

[JamesEB]

Thanks. Sounds good.

I haven't got a pressure washer and I don't think anything will fall off as it is all under several layers of thick smooth masonry paint.

I did ask two paint shops before and one said to paint over it and the other to paint it with Zinsser Bulls Eye 1-2-3 and then paint over it.

Thanks for help
JamesEB

 

[misterhelpful]

If it's painted then it should be easier to clean. Whoever tells you to paint over it without removing/killing spores is setting you on a bad path. It may cover, but the spores will continue to grow under the paint and then end up causing the paint to flake and peel.

BTW, Jeyes Fluid, as mentioned by Nozzle, does the same job, but has a strong smell that some people love and some hate.