[David stewart]

Anyone do this for customers?
What's best solution to use and do you just use a scrubbing brush or what?
Any info much appreciated

[DaveG]

I've used bleach before, but obviously not above a flower border!

[wfp master]

small waffle cloth.

[David stewart]

I'll bear that in mind mate.

What on earth is a waffle cloth wfpmaster? Lol

[Ian101]

speak to a pressure washer chap and get some hypo 

[8weekly]

Be careful using hour brush or you could expose the steel pins and risk damaging windows.

[David stewart]

speak to a pressure washer chap and get some hypo 

Must get a jar of it mate

[Paul T]

Old vikan brush

[amayze]

We used hypo mix and a good old fashioned hard scrubbing brush, came up a treat......but just watch out for any flower beds !

[SeanK]

Was talking to a customer who used a chemical to remove moss and algae from
his flagged area.
He just sprayed it on and left it.
Flags came up as like new so I cant see why it wouldn't do the same for concrete sills.
No scrubbing needed and its pet friendly.
Cant remember what brand he said it was but there are plenty off them out there
try Amazon for feedback.

[craig trevain]

Brick and patio cleaner, its a hydrochloric chemical, but wear goggles.