What is a good ratio for 12.5% SH, water, and surfactant to clean roofs and one for a house wash?
3-4% works great for me. I add differing amounts of surfactant every time. I dont measure it. I use cling mostly
Here’s a link from this site about roof mix. Probably 100s more. House wash also discussed several times. This site is a gold mine. Use it
50/50 water and 12.5 for roof.
33/66 12.5 to water for downstreaming house
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Thank you
50/50 in my opinion is too high a percentage for roof cleaning. A 3-4 % is what we use. 4% on a more heavily stained roof. The lower percentage you can use will help eliminate problems with the shrubs and grass.
Also when spraying do not flood the roof. Put a light application on the whole thing, wait 10-15 minutes and touch up any spots as needed.
Also use qypsum pellets by the downspouts and either plant wash or whatever neutralizing product you wish. These help save on those dreaded call backs.