So, I have somehow become the banking industry go-to guy in my area for cleaning mold/algae off block limestone buildings. The stone is fairly porous and rough on the surface. Currently using the SH/Lemonator mix with success but feel I am going through more SH than I should be ( you have to run at least a 50/50 mix to get the mold off. I have tried weaker mixes in every dilution and application with repeated applications scenarios and found only a strong mix does the trick). I am starting to think perhaps I should be using roof snot or some other thicker surfactant to make it stick better. I have tried increasing the Lemonater contribution to the mix but it just seem to make rinsing take longer, not really aid in sticking. Anyone have experience relevant to cleaning this stone?
Been several in depth Limestone discussions past year. Check the search button. Too long for me to repeat everything, but Elemonator would not be my soap for that application.
OK, I’ll bite. What WOULD be your preferred soap? Snotmenade?
Probably ebc
He recommends EBC.
If it’s got soot on it, use EBC. If you just want the SH to stick use the roof snot or use both if you have soot, which he very well could have on those buildings if next to hwy or they’re old, then you get best of both worlds, lol
This is an example of what I usually see. The bottom left corner is what I cleaned as a demo for this location. No soot, just mold. This particular job, they have tried to clean it themselves with a cold water pressure washer, which does knock off the loose surface mold, but not what is in the pores. Usually no soot and surprisingly usually not a lot of dirt. Just mold deep in the pores.
Note - most around here already has the orange coming out, I just try not to add more, but cleaning, rinse and then neutralize.
I have been using Oxalic Acid (1/2 cup per gal water). Is this strong enough to neutralize a 50/50 SH/Water mix?
Easy one, bottom left looks fine. Go with the mix you suggested for the pump up. May not even need the hydroxide, but won’t hurt… Let dwell about 10min, rinse medium pressure. The real dark spots, may have to hit twice.
Take us an after. You’ve got this.
