Coating a house and keeping it wet at a straight mixture is very expensive in OX Nox. One company said to do one home, it was like 600 dollars in Ox Nox alone.
There's a lot that goes into what ratio to use. If you don't mind scrubbing a little bit, you can go with a weaker mix. Brushless needs to be stronger. Do a test spot on one shutter to see what ratio you like best
