First Roof Job in the Books

I quoted a roof job & up sold a house wash. I went with a 5% mix and applied with my 12 volt set up. The application went well and stuck, but the roof was really dirty. I did a quick partial rinse, but figured I will let Mother Nature take care of the rinsing. We are not suppose to get rain until maybe Sunday. I am not to happy on the results and will probably need another coat due to being really bad. How much will the SH degrade over time?

I hope the second photo isn’t the after pic before you left. You missed sooo many spots.

I think the second photo is the before.

Correct, I figured there would be a couple of spots I need to touch up. I was going to wait for it to rain to give it a good rinsing & then go back. Will the SH degrade enough to not harm the plants by the time it rains?


I wouldn’t worry too much about the plants since it has been on the roof for awhile.

How old was your SH? I wonder if you really had 5%. How long after application did you take the pictures? I usually spray the whole roof and then will sometimes do a second light coat over the bad areas.

The general rule is “if it turns brown, it’s coming down, if it’s still black, you’re going back.”


I just got the SH from my pool supplier and it suppose to be 12.5%. The pictures were about 30-45 minutes after applying. Good info.


I will definitely remember that!!


I will go back to do a light coat maybe this weekend or next week. Home owner was very cool and understood it may take more than one application. I just went and did 3 quotes and landed them all. Two house washes and a roof wash. Learned a lot on this website by reading, reading & more reading.

Thanks for the help


You can normally take care of it all the first time you wash it. As Steve said just make sure it turns brown. If it’s not, spray enough applications until it is. Give it like 15 minutes dwell and, if it’s still black, spray some more.

Way to go on landing all 3 of the quotes!

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Great info and thanks again for the help!

Enjoy the weekend

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I never get off the ladder until the black is gone if any question. Easier to stand up there and wait 5 min than going down and back up. Hot day the SH will degrade a lot within a couple of hours. You’ll learn the more of them you do. You’re losing money if you have to go back. Hope you had someone rinsing for you since no gutters.


Racer, thanks for the advice. Yes, I had a ground so the plants & ground was saturated. Plus we used tarps to cover the front of the house.