Cleaning/removing alage (??) from aluminum siding

[BAM6I4]

I have aluminum siding and its definitely looking worse for wear so I am looking at my options.

1st obviously would be to replace everything...does this usually go over what I have or do they remove and replace? Also, would you go with aluminum or the plastic or do I have any other options?

But since that sounds expensive and its honestly not that bad except for the north side of my house...I'm wondering how I could go about cleaning it?

No idea how old the siding is but I've been here a few years and have noticed on one side (north) of my house its turning slightly green in color. (white siding) I believe its because this side doesn't get as much sunlight as the others but honestly have no clue. There are no gutters on this side of the house so it's not like something is leaking down on it but its getting bad now and I need to do something.

Can I just powerwash the entire house? Should I break out a scrub brush and dawn soap? Bleach? What?

Thanks for any help

[Bibs]

I had the same problem. I called the local siding wash guy, and his 2 man crew power washed with their solution, scrubbed every inch with ladders and brushes on poles. Came out looking brand new.
He rinses it with a "sealer", as he calls it, which repels the water/dirt for a period of time...seems to work. They also squeegeed the windows when they were done.

After his crew did the big scrub, I periodically rinse the siding with my power washer (maybe twice a year?), and it seems to keep pretty clean...

It took his guys ~7 hours, and he charged me $500 cash. It was worth every cent. Those guys worked like dogs.

[BAM6I4]

Appreciate the info!

Is your siding Aluminum? Just wondering if that would make a difference.

[Bibs]

20 year old aluminum...they did a great job bringing it back to life.

[02reflex1.8t]

I have never personally used it; but, I hear good things from people about a product called Spray and Forget.