There are multiple products but they aren't a 100% solution. Powerhosing patio is best and environmentally friendly, Epsom salts and vinegar works and is environmentally friendly. But be careful it kills everything and is a pet deterrent.
For roof a strip of copper, not cheap, will work, place where slant on roof begins, there must be some fall otherwise your roof would fill with water.
Again Epsom salts and vinegar.
Epsom salts can be replaced with rock salt but its very toxic to wildlife.
These are non chemical ideas, I garden organically its twice the work but better results.