[gizmofixer]

Great topic in this time of 'honey-do' projects!
My house and deck need regular cleaning due to extensive tree coverage.
Over the years i have experimented with a number of different products and mixes.
Best solution has been a 50-50 mix of Clorox Outdoor and water. It's formulated for siding, decks, furniture etc.
I apply with a bug sprayer, let sit for 5-10 minutes then rinse with the power washer.
I can literally watch the dirt, algae, mold and even light moss just run off down the siding.
Pressure wash only as a rinse, no up close blasting required.
Bleach, even a low concentration, has done bad things to the grass and plantings.
Other products and mixes are OK but the Clorox Outdoor has been BY FAR the best.
It works great on my composite decking and even the concrete pads by the garage and steps.
Enjoy and easy project with immediate visible results!
--p