Here is a little background on how I started Roof Sparkle. A company that’s making cleaning products asked me if I could make a video for some of their cleaning products. Now I won’t go into details on who they are but they had a roof cleaner that involved the use of a power washer. A big red flag in my eyes. Being a contractor for years, I knew right off the bat that was a big no-no.
So the next question I asked myself what’s that black stuff on the roof. Well, it’s mold. And what kills mold, bleach right? Well, as true as that is bleach is only made up of 5-6% Sodium Hypocrite. And that’s great for your whites and around the house but not on your roof.
For the roof, you will need something a lot more powerful. Some of you may know it as pool shock. This is made up of 12% by weight “Sodium Hypochlorite”. But because it’s as thin as the water it will run right off the roof and not really have the time (five minutes) to do its job. So we have to thicken up a bit. The best way, add some liquid dish soap to the mix to help the SH stick to the roof for more than one second. You can go into any pool supply and ask for a gallon of shock, for about $4.00 per gallon. This is just a heavy-duty version of household bleach. And no Walmart does not sell this or the big box stores. This method will remove algae from a roof.
Now, of course, we buy it from the manufacturer and by the truckloads at a time.
Applying It
When we started we used a regular bug sprayer. Use a three gallon pump sprayer, use one gallon of SH and two gallons of water (H2O) add about 4 oz. of liquid dish soap and spray from the roof top working your way down.
DON’T
- clean your roof when it’s super hot out in the baking sun. It will kill the SH and dry before it’s clean.
- Don’t touch the SH with bare hands. Wear gloves and eye protection.
- Don’t spray your roof down first with water to cool it off.
Comments ( 173 )
At what temperature does the mixture start degrading? I live in New Hampshire and have about 1/3 of my roof in moss, thanks to some Maples. I’d like to clear the moss as soon as possible to save money on my insurance, but am concerned about the temperature.
Anything close to freezing is not good for the SH
Can I use this mixture on my tile roof?
Yes, but for tiled roofs you may need to add more SH / pool shock
Could you tell me how I could go about starting a business doing this? Like how much to charge and what type of setup you are using in the video?
Yes I could. However not for free and would be done via email / phone and pictures of how to setup a trailer or van. $500. and make it back in just one roof job.
Dominick! Thank you for sharing your expertise! I will let you know how it works out for me!
Hi Dominick,
We are going to try a bleach and water solution on our roof to get rid of the moss. Any advice you can offer would be appreciated! Should we rinse the roof off with water after the bleach has been sprayed on? How long should we let the bleach solution sit there? Thanks!
Using hot water will kill the SH. Use the water out of your faucet. Rinse the moss off.
2.2 gallons of normal 6% bleach mixed with 0.8 gallons of water will give you 42,000 ppm.
That’s with the realization that 6.00% sodium hypochlorite is used, and this is equivalent to 5.80% available chlorine. Available chlorine is the amount of chlorine available for sterilization (or moss killing, in this case).
Hi, could you tell me what mixture you use for power washing vinyl siding? Thanks
You would not use this in a power washer.
GREAT videos!
Thank you
I ran the calculation and it comes to 38,100 ppm both ways.
But maybe you’re doing something different.
42k PPM is from 15%
How do you keep the bleach from hurting the plants, grass or leave obvious streaks on surfaces below?
Is it best to clean the roof then in the AM or PM, after the sun goes down sometimes the roof remains hot for well into the night.
Thank you so much
How large of an area will a 3gal batch of cleaner cover?
When we go out to clean a roof there is always two guys on a job. One is the guy on the roof spraying / cleaning the roof and the other ones job is to spray everything and anything that could get over sprayed with the roof cleaner.
So, you would wet down all plants and then rinse them again once you’re done cleaning the roof. We clean roofs all day long. But once in a while it just gets way to hot. At that point you really can’t walk on the roof anyway without damaging it because it’s way to soft. Hope this helps… Dominick