How much Sodium Hypochlorite

I have a simple question or two…

5 gallon bucket, low pressure soap attachment on pressure washer…how much of the bleach do you use with the water for a reasonable dilution. (not taking into account the settings on the dilution knob of the pressure washer) as well as the Simple Cherry??? (see question below)

Simple Cherry…acceptable alternatives??

Thanks in advance

Eric J

(I don’t have a roof pump yet and I’m referring to cleaning a mildly discolored comp or shake roof)

Depends on how dirty the surface you are trying to clean is.
Try 3 gallons of sh and simple cherry. sh[pool chlorine]

Are you using the strong stuff?

You can not get a strong enough solution by down streaming or upstreaming whatever you are doing. Even if you put straight 12% sh in a 5 gal bucket you will only get approximately 1% solution on the roof. ( you need to do a bucket test to find out exactly) To properly clean a roof you need around 4% sh on the roof.

Wood shake roofs are different from shingles. Do some research before doing shakes.

How bout If he does not turn the pressure washer on but the water is on and downstream injector is in the bucket with 12.5%? I know when I have accidentally left the downspout injector in with the water on… the solution still goes up the hose and out the gun at a high solution rate… Has anyone tried this before? It’s a cheap alternative but has anyone had success using this method for roof washing?

From my experience with our power sprayer:

Whether the power sprayer is on or off, you still need the hose connected and turned on to siphon out chemical from a downstream injector.

The term “downstream” applies to a chemical injection system that comes out after the water has moved through the pump. No water, no injection. The water is what siphons it out.

It would use the same dilution ratio either way, just no power.

I apologize. After re-reading your post I saw you said with water on. I still believe it is the same dilution.

Do a bucket test and see what you get

My mix ratios are here, SoftWash Roof & Exterior Cleaning Systems

hope it helps,


Thank you

Eric J

Thank you.

Eric J

I haven’t bought any yet. I can’t afford the roof pump systems yet (soon, but not yet) and want to get the best cleaning solution to downstream on my 4 gal/min 4000 psi pressure washer.

Eric J

The second part of the question, which is equally important to me is what is a good available alternative to Simple Cherry, as I’ve never seen it around here?

Thanks in advance.

Eric J

I would love it if you tried my Green Wash. It is an all in one additive for bleach based cleaning solutions.



Call Bens Cleaner Sales in Seattle. There are in the shadow of Safeco’s fields roof. Ask for Russ or Chris. If you get Chris tell him his sexist customer sent you.

=) Rodger…and thanks.

I will AC, thanks!