Hard water stains on vinyl siding

I have a house with calcium or hard water stains on white vinyl. I will be down streaming with my pw. Any chemical suggestions, or is it gonna require brushing?


would oxalic work?

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How can you see white hard water stains on white vinyl?

I would try a mild oxalic mix on it. Do a test spot first.

It shows up as a light brownish calcium looking buildup. Not really sure it’s hard water. The customer thinks it is and the sprinkler system hits those areas. They are on a well and this area is typically known for hard water. It could be a sulfur stain but the is no sulfur smell in the water that I could see.

I’ll try oxalic…

Phil try and get a before and after picture… I would be interested in seeing it.

I will. I spoke to Robert over at Powerwash.com and he wanted a pic as well. I’ll get a couple.

no possibility of rust?

Don’t think so. Nothing metal nearby. This place was the first power wash job and or course it has to be a tough one. I never get the easy ones first. What would be the fun in that? lol

Cool, post some before and after pictures. Sounds like a good learning experience.

gotta be honest with you phil. you’ve been stringing us along for 2 weeks now. no pictures, no results, no answers… nothing!

i’m dying to know whats going on

Sorry guys I have been busy. I’m going back to that job next week. I’ll get em then.

Pics? hahaha:D It’s been a while, but if you can find the pictures laying around, it could help us all.

Sorry guys, No pics. I lost the job to another pressure washer. I often wonder if he was able to solve the issue. Kinda frustrating, but I was at a loss. Not as experienced as many of you here. Thanks for helping anyway.

sounds like rust from hard water in the sprinkler system

That is very likely. The house is on a well and as my house is, the water is very hard.

If it is, what would you use?

Oxalic should do the trick…mix 8-10 oz per gallon of water in a pump up…I have run into the same thing doing residentials on well water

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Oxalic always helps me