The exterior of my house is stucco and is about 20 years old. There is discoloration/dirt under some of the window frames and along the base of the house. What is the best way to clean stucco? Should I powerwash it? If so - I don't want to damage the stucco - is there a particular nozzle and maximum pressure that I should use/be aware of? Or is it best to use a spray on/hose off cleaning solution? If so, any tips on brands or products woudl be great! Thanks for the help!!!
powerwashing will definitely work, no doubt there. If it were me, I'd go rent a strong (3500 psi) power washer and do it from a distance (couple feet maybe, if you put it right up to the stucco you'll def crack/chip it). A hot water pressure washer would work better, but they don't have those where I rent stuff.
I'm sure that there's a bunch of chemical approaches that woudl be applicable too, but I'm ignorant of them so I can't tell you much about them. I'd just go rent the pressure washer if it were my house.
as far as nozzles/pressure though, you'll be able to tell when you're doing it what is right. You'll find, based upon the power of teh washer, what tip gives you the best coverage while still providing the pressure to clean it. Wider tips give you better coverage, but less power, so you'd just change tips/distance til you find what's the most efficient.