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 )
hi dominick if we buy the sodium hypoclorite liquid do we have to mix that with water ….what i exactly need for 10 gallons of water if i use liquid sodium hypochlorite
You must only use liquid. For free I’m only showing here how to mix three gallons at a time.
I have a 1 Gallon bug Sprayer. I don’t have a 3 Gallon one. If i mix 1 gallon of liquid pool shock with two gallons of water inside a 5 gallon bucket. Can i pour 1 gallon at a time into my bug sprayer.. Will i mess up the ratio? Thanx for the help
Try a third of SH and the rest water.. or for a stronger mix use 50/50
You mention mixing the sodium hypocrite with some liquid dish soap to thicken it up a bit. Do you have a recommendation regarding what dish soap and are you referring to regular dishwashing liquid or dishwasher gel? Also, what is the mixture ratio of sodium hypocrite to dish soap?
Just use a dish soap without any bleach in it. The soap is only to help aid the SH to stick on the roof a little longer, that’s all. A cup is plenty on the above mix
Hey thanks for the information. How about Vinyl siding? Will it harm or discolor it? I was told that 10 oz. of Alcohol, Murphy’s Oil Soap and a gal of bleach does the job but I don’t know the ratios.
Careful what you mix with bleach. I’ve seen some siding change to a orange color before. But 99% of the time it works really good.
Sorry, but I don’t think this was clearly asked before; I’m having trouble finding exactly 12 or 12.5% Sodium Hypochlorite (even in my local pool shop). However, I have found 10% options. Would that work?
No 10% wont work. Only SH will work. You’ll have to keep searching.
Will the SH solution be harmful to animals? If I leave the liquid on the roof and spray the moss off after it drys will it be safe for my dog in the yard?
Thanks.
I really can’t answer that. Your dog eat some rat poison the same time you’re cleaning your roof and it’s my fault. Sorry. Just spray and rinse well. SH is a high power bleach. And bleach would kill if you swallow it, right.
I am having trouble locating the 12% sodium hypochlorite. Is there a site online I can order it from? Keep find calcium hypochlorite anywhere from 48 to 90%. Thanks.
Go to a pool store and buy liquid pool shock.
My situation was complicated by having a slate roof I couldn’t walk on. I climbed a ladder to the eaves and used a $15 WalMart SuperSoaker filled with 10% pool shock and the algae was gone
immediately. Yeah I know…it’s a bit hinky but if anyone can figure out a better way I’d love to hear it.
Love it. Great idea
I’ve received three quotes, and the price each is $1200-1300 which is out of my budge. My roof is a 10:12 pitch, and somewhat steep. I am trying to figure out a way to spray it myself, without too much mist and overspray, while standing on a ladder. I noticed Northern Tool has “tree sprayers” that shoot 2.2GPM or 5.5GPM out at 60psi.
Do you have a solution where I can do this myself from the ground without walking the roof/
That seems way too high of a price. And no, without spending big bucks on air pumps and special equipment. Send me a picture of your house and I’ll tell you what it should cost.
Can I send you via email? Don’t want to post my house on a public forum.
on the bottom of this page you’ll see “contact Dominick” Use that.
Thanks, I just sent you 4 pics.
Same thing for the others as well.
Hi – no water. If we dilute, can’t I buy just cheapo 8.25% bleach?
You need to read what I wrote again. It’s done by weight not volume. Not adding water is VERY DANGEROUS
Thanks for the pic you sent of the ladder, I am going to try that.
I bought a bug sprayer and a gallon of Shock Chlorinating Liquid for Pools (10% Sodium Hypochlorite).
I mixed about half a gallon of undiluted Shock and a half cup of Liquid Tide Free and Clear into the bug sprayer and sprayed a small patch.
Within a few minutes the solution turned very warm to somewhat hot. I am not sure what thermal reaction is going on, but the bottle is sitting outside now.
how much water did you add ? A 1/2 cup is a little much.
You have a very steep roof no doubt about it. But it’s also a single story. What you would do is get a long extension ladder and lay it right on the roof and spray it with a bug sprayer.
My question is regarding using the “pool shock” treatment on a low pitch, tar, pea gravel roof. I can’t just brush the moss off so do I leave it on until it’s dead and rake it out? Will that damage anything? Do you have any suggestions?
Thanks
Brush the moss off, Then spray the roof with the cleaner then rinse after 30 minutes.