Wet and Forget is a great product but it is not a fast acting product.

My cabin is white siding and it gets mildewed and nasty on the backside.
I spray it in the fall and it is nearly clean come spring.

These are a number of years old and it’s the first time I used it so it had a NUMBER OF YEARS of build up.
All I did was add the Wet and Forget to water in a sprayer and I sprayed it on in November. No scrubbing no agitating. Just sprayed it on. This is what it looked like prior to spraying


And come May this was the result likely looked like this in March or so. And now that I do it every year the final result looks even better as there is less build up.


Again these results are with ZERO AGITATION OR SCRUBBING.
Now I do it every year. I am half tempted to do it in the Spring and Fall.

quote:

Originally posted by shiftyvtec:
It is generally Sodium hypochlorite with a surfactant.

This is what I used, I mixed 3 gallons of 12% sodiumhypochlorite with 12 gallons of water and a 12 oz bottle of dish soap using 6 gallon plastic buckets I had laying around. I purchased a dewalt hand held power washer (flex volt version) which maxes out at 1000psi and feeds from a bucket. It worked better then an injector for a power washer I could throw the mixture 25 feet to hit the peaks of my house.

I kept all the flowers and bushes drenched before I sprayed so the bleach wouldn't kill anything. After sitting for about 10 minutes and not allowing the mixture to dry on the siding, I used a special tip called a jrod for my powerwasher that allowed me to rinse the house off without having to adjust down the psi from 4000 so that its safe enough to hold your hand infront of the nozzle and still shoot the water stream 25 feet just to rinse. Never use a powerful presure washer against siding.

This removed thick algae from my north facing side which was almost green opposed to my grayish siding, it also removed some dark black spots from my gutters, and cleaned a lot of dirt and dust from my sidding in general. There is a special chemical for gutters that I didnt bother with as the results were ok for me but not perfect like the siding ended up.

It was easy, the hardest part was researching the mixture and setting up the hoses for my presure washer.

On my 1st house that had vinyl siding-I used an orange bottle that was squared at Lowe’s-don’t remember the percentage but it was strong bleach - sodium hypochlorite

My other homes were brick and didn’t have any moss/mold.

I have white vinyl siding. All I use is regular bleach, cheapest I can find, and water. I mix half and half, bleach and water in a pump sprayer. Don't need high pressure for it to work. I spray it on and may or may not rinse it off depending if it's going to rain later that day or tomorrow or so. Should do it once or twice a year. And I think the white siding is more forgiving than maybe something else that might show streaks and whatnot.

Been here 20yrs this year and I pressure washed for several years before going to the bleach and water in a pump sprayer that I'll stick with. Easy peasy.

EDIT: Just remember, it's bleach !!! ... So keep it close to the wall. It MAY temporarily kill grass and weeds as it drains down into the soil below. Especially if not well diluted with rinse after about 10min as some do. But killing grass and weeds within just a few inches of the foundation, even if seasonally or temporarily is bonus to me. And don't wear nice clothes that might get a few sprinkles here and there depending on wind direction.

quote:

Wet and Forget is a great product but it is not a fast acting product.

Works well for me... mold didn't get there in a day, so I can wait for it to go away. I generally spray every other year. Texas coast.

quote:

Originally posted by 12GA:
30 Second Cleaner is what I use on my white vinyl fence. Spray on and rinse off with a hose. It works as advertized.

This is good stuff we use it all the time here in Moldlando! It won't kill plants and grass it is made for outdoor use. Wet and Forget works but not as well as the Outdoor 30 seconds Cleaner.

I get it in the large concentrate and mix it up 50/50 in a hand held pump sprayer. At that strength it does the job b-e-a-utifully..... Use it twice a year to get rid of the mold and dirt on the pool screen, just mix it up and go spray everywhere and walk away, no need to rinse it right away let it dry and do it's thing.

They do have it in concentrate with the hose adapter if you don't want to mix it up in a pump sprayer ready to attach to a hose, if you have to hit things higher up. I use that for the top of the pool screen.

30 Second Cleaner Hose Spray Bottle

quote:

Originally posted by 6guns:
The stuff I use is called, 30 Seconds Outdoor Cleaner. Works excellently!

I get it at Lowe's.

I used the same stuff. At first it looks like it’s not working but then it looks like brand new siding. The spray jugs that you use on the end of your hose do not last long though. Get more than you think you need.