Surfaces you can't use SH on

If this is answered already I apologize, but is there a list of surfaces you can’t use SH on? I know I’ve read certain types of painted surfaces, etc. If it’s out there already, could someone drop a link to that thread? If not, could someone help clear up common surfaces that we shouldn’t softwash with SH? I know 90% of my business will be plain old vinyl and concrete which I know are good to go. Just wondering what I should stay away from. Thanks for any help. (my profile says I’ve only read 1 hour but I read probably 30 hours in the shadows before I created my account)

Copper for one.


I’ve read Sherwin Williams paint. Always do a test spot in an obscure place first. Havent run into any weird issues so far, but I want to be proactive about not doing that so I always bring a spray bottle/pump sprayer for a test.

I’m struggling to even make a list, other than the obvious ones. It’s more the strength of SH you need to be careful with.


Thanks Dallsheep. Do you just ask the homeowner if they used Sherwin? Or how else would you know it’s Sherwin? I guess like you said just play it safe and do the spot test to see if it distorts the color

Thanks dc. That’s a good one to make note of.

Don’t use SH near a koi pond. Make sure it’s completely covered and away from any run off.


I’ll ask but like you said .ost don’t know so it always comes back to a test spot.

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can’t use SH on copper eh, so how do you do cedar roofs with copper gutters?

I won’t, personally. If it has copper I won’t touch it.


Tape every square inch of copper and charge $1,000/sqft


It’s crazy just how small of an amount of bleach will kill fish. It was just a few weeks ago at U.C. Davis research lab where they killed 21,000 fish. Why, because some normal tap water that has trace amounts of chlorine back flowed into the tanks. The water we drink everyday will kill thousands of fish.

” Overnight, however, enough chlorine had entered the tanks for there to be a similar amount to that in tap water — a dangerously high amount for fish, Dr. Brignolo said. Fish are not supposed to be kept in water containing even small quantities of the chemical.”

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Wow 1000 sq ft labor intensive

Don’t use sh on cedar you will dry it out, it needs oils to keep it preserved…

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This is why we want nothing to do with koi ponds, ever