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Pressure wash or other method to remove moss?


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The Hen that laid the Golden Legos
310   0
Aug 9, 2012
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Live on the river where the summer humidity is stupidly high. I have aTennessee rock slate style walkway to the house. Spent a day last year on my hands and knees scrubbing the moss off with sodium bicarbonate and vinegar. Worked great...until the humidity came back.

I want to use a pressure washer but had a bad experience using it on concrete at my old house. The nozzle pressure was so high and concentrated, all I did was put lines in the concrete. Would this happen to rock/slate?

I don't own a pressure washer so not sure of all of the available attachments to alleviate this problem.
Most rock/slate generally has a harder surface than concrete.

Highly recommend one of the new Ryobi electric models. They're a bit gentler than most gas models. I used to use a Honda gas-powered 2300psi unit for everything. Had a chance to try a friend's 1800psi Ryobi electric, and it was a pleasure to use. Have my own now, and that's all we use anymore. Cleans mildew off concrete, decks, great for getting mud off the tractor, etc.

Only drawback: About a 50' limit on water supply hose length. Longer than that and it won't supply enough flow to charge the pump.
get one of those disc that goes round & round
they work great and are fast and can even be used on wood deck without damageing the wood

There's a product on Amazon it's called Outdoor Cleaner. I took a chance on it to take the green mildew off the siding of my house on one side cuz the Sun never hits it. You spray it on leaving 30 seconds and it washes everything right off. My hose didn't even have hardly a trickle of pressure. I had to put my finger over the end of it just to get some to spurt out but that was enough water to just rinse it right off. I only have one spout on the outside of the house and it's out back. So I had to link a couple hoses together and I think one of them is stopped up. But it does exactly what it's supposed to put it on wait 30 seconds and it rinses right off. I guess it depends on how much Moss or mildew is on there. If it's real, real heavy I guess the pressure washer would be the best thing but I would give Outdoor Cleaner a try. It's relatively cheap and easy to do.
Thanks, but I do not want to use any type of toxic chemicals (^ sodium hypochlorite-is diluted bleach), as the water will drain down into a river, and that is where I go fishing.
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