Roof Wash

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Cant you just spray bleach on the roof? I’

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I wouldn't spray straight bleach, but cut it 50/50 with water just to be safe. It will still get to the mold or mildew on the shingles.

When I wash my house, I use a mix of Jomax, bleach and water in equal parts in my pump sprayer. I'll spray a section and let it sit for a few minutes to give the stuff time to work and then use my pressure washer to wash it off and the results are very good.

They are using oxygen bleach mostly (OxyClean). I rigged up my own roof sprayer with an old rain barrel and an electric transfer/pressure booster pump to clean my roof and my parent's roof of that black mildew/mold staining. Just spray, let it soak for 30 minutes or so, then rinse. Water coming off the roof looked like coffee. Took few applications to get the worst spots clean but worked well and is safe of plants and surfaces near the house.

Try the Jomax/Bleach/Water mixture, and don't go heavy on the bleach. You don't want to dry out the shingles. Best way would be to get up there and spray it with a pump sprayer, and then hose it towards the ground. Don't spray the hose upwards or sideways

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It can be if used by people who don't know how to use one. You can use the widest fan nozzle that spreads out the spray and then don't put it close to the shingles where the pressure will knock off the granules. Hold it far enough away that you get a nice stream, but not enough to do damage.

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You’re still unnecessarily knocking rock off and cutting down the life of the roof

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There’s some stuff out there specifically made for that. I would be very careful what I put on there and what you used to wash it with. Especially if you have any type of warranty

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10-4. I've also read it's important to kill the algae as it, too, loosens and leads to the aggregate detaching from the shingle. I know this, my N-side gutters are consistently full of aggregate, my s-side not nearly as much.

Go to tractor supply and buy a cheap 12 volt sprayer, even a 1gpm unit and 15 gallon tank will do. A 2.2 and you'll be done in half a day. Go atleast 50 percent bleach, most clorox you see on a shelf will be less than 7 percent chlorine. Add a good surfactant like dawn and some TSP if you want, agitate it real good. Do one side at a time and let it dwell. You go lighter and you may end up doing a couple runs. The hotter the temp outside better the bleach will work too.

Most roof cleaning guys are using 12.5 percent chlorine and throwing really hot batches on there. Some roof cleaners don't even rinse. Zero reason to even use a pressure washer, if you do use your soap tips only.

Most important step is to keep all foliage, gutters, soffit/fascia, etc. wet. It will smoke plants, obviously evergreens arent as susceptible as say your pretty annuals.

I own a pressure washing company but do not do roofs, have in past but something not worth headache. This thread has me remembering I need to do my own roof once the Christmas lights come down.

I have used the wet and forget on concrete and on wood. The stuff works! It's not like bleach where you are going to see the results an hour later but give it time to work and the algae and moss are gone.

Drop, if your looking to get the tiger streaks off, which I'm assuming you are I would go with purple power or any butyl based degreaser. Spray on with pump up sprayer after everything has been wet and brush with soft brush and pole after it dwells for about a minute or two. Carwash type brushes. Rinse off with hose or pressure washer, start at around 35 percent purple power and work your way up stronger if necessary. Elbow grease is key and do like 15 feet at a time at most. If you let sit too long or use to hot of a batch it will strip paint. If your gutters have been painted outside of the original factory color/dip, I do not advise trying to remove streaks

There are stronger and better chemicals marketed towards professional cleaners, but for your use it's not worth buying a gallon or 5 of something good. You're going to get purple power at autozone for less than 10 or 20 bucks.

Removing streaks is way easier in the summer time too btw. Tough in these conditions.

Drop, all gutters are different. Some are a breeze to clean and literally it washes right off. Others you can go over continiously and strong and never look good. I dont push that service because of the unknown.