Soap for hardie plank

Sometimes when I wash hardie plank with sh downstream it still looks dirty does anyone know a good soap to use

Define “still looks dirty”. Got any pics?

I use my normal HW mix with Elemonator on lots of Hardi plank houses and they always look great. I’ve found with that siding I go lighter on my mix and rinse right away and rinse a lot. I’ve never had that siding get nearly as bad as vinyl, so I never need a strong mix.

Ok where can I get Elemonator ?? Power Wash store here in Nashville doesn’t sell it. I appreciate your feed back. Everything I clean looks good except sometimes the hardie plank on certain sides of the house looks dirty or dusty.

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I won’t use SH on Hardie, the crappy paint they use has spotted on me before. We have a whole ‘manufactured town’ of the stuff, I just do a soap and rinse.

I’ve washed plenty of Hardiboard siding with SH and never had an issue to date. But, I also test things before I go spray them with chemicals.


Even the blue shades?

Yes, even some light blue. Never anything even close to a dark blue though. I’ve even washed one red hardiboard house. Luckily they had a complete panel that had come loose and that side of the house was being expanded so I tested 4 or 5 different strengths on the test panel and then tested just my HW mix on that side before continuing on to the rest of the house. The red test panel turned pink with anything over 3% on it. I was also cleaning the green metal roofs on the house and the shop so I needed to now how hot I could go before I could have issues.

I have a Gen 2 with a proportioner on it . Thanks for letting me know about the color changes I didn’t know that could happen