Long time lurker. I was basically able to build my pressure washing business between this forum and YouTube. For the past few years, everything has gone pretty smoothly.
I took this job because it had potential to be a yearly client, knowing the dark paint could be rough. I gave her an estimate over the phone. The house had a decent amount of dust on it. I’m in Missouri and we had a bunch of dust blow in from Oklahoma a few months ago.
I hit it with a house wash mix via downstream injector. When I got done there were these spots on most of the house. It’s not visible from a few feet away but it is when you get close.
Anyone seen this before?
The paint is a Sherwin Williams Acrylic Latex.
Could these be hard water spots?
Is it possible that my house wash mix had been sitting to long, degraded, and caused this?
When you wipe it off with a rag it takes a bit of elbow grease to get it off, its not like wiping off dust.
My next thought was oxalic acid. Thoughts?
Darker colors can show and leave mineral deposits when dried….depending on how hard your water is in the area you’re in. You can look it up here on the forum……if that is what it is. Looks like it to me…did it look like that before you started?
It didn’t look like this prior. I did research but I couldn’t find anything for removing mineral stains on painted wood. Just want to get some opinions on what it could be before I spot tested some oxalic on it.
Light acid will remove water spots but you would need to rinse with low tds water so not to have it happen again. In my terms and conditions I warn that windows and dark colors could spot depending on their water source or condition (tds). I can’t control water quality coming out of the tap….I just educate them on the possibilities….so it’s up to them if they want to proceed. Get a couple every year……
Try a small area first like always then yes try a rinse aid. You will want to dilute it also. I think ebc glide is what window washers use to help reduce spots? @dcbrock may help on name if I got it wrong
What kind of setup/filters do you use? Got some pretty bad spotting on a dark brown house a couple weeks ago and looking for a solution because almost every house in my area has hard water.
Most of the older houses are light colours, but seems like every new house going up is either black or dark blue/green/brown.
