I have seen a few roof cleaning products that are sodium hydroxide based. Does anyone know what to mix sodium hydroxide with if I buy the raw material.

I'm assuming I can dilute it with water but how much?

I saw Pressure Pros recommend sodium hydroxide and butyl(for concrete I believe). Is butyl the full name for a chemical?

I would love to hear from anyone, especially Pressure Pros and Carolina Pro Wash. I've been reading these boards for awhile now and you guys really seem to have your @#$* together.