[Paul79]

Does anyone know what this is and how it can be cleaned on this wall:



This is the orignal wall before it got pressure washed:



Just to add, this isn't a customer I was just testing the pressure washer on it but was suprised at how much was left on the wall and no amount of pressure would budge it!

[Mike Halliday]

It’s organic growth, lichen, ‘black spot’ , easiest way to remove it is with sodium Hypochlorite which bleaches it out. A very easy job

[Smudger]

but the op doesn't believe in chemicals...

Darran

[Paul79]

It’s organic growth, lichen, ‘black spot’ , easiest way to remove it is with sodium Hypochlorite which bleaches it out. A very easy job

Thanks Mike, this isn't the first time I've come across this stuff. Will research into Hypo and accept the fact that it needs to be used on some jobs.

[Mike Halliday]

This is an example of what hypo does, no powerwashing just treated with hypo

[John Kelly]

Spray it with Algex https://www.restormate.co.uk/epages/15094.sf/en_GB/?ObjectID=18123735

[SB Cleaning]

I did this today,  it was covered in black lichen, pressure washed with turbo nozzle and hypo applied after, the after photo was still wet it would of looked a lot sharper when dried, customer wanted the moss left on the walls.

[Smudger]

Lovely job as always - instant results - customer happy - get paid - fab!

none of this faff paying £50 for 5 litres of jollop that £2's worth of SH won't do, and does it better

Darran