4 Ways to Clean a Roof

Method 1: High Pressure (Pressure Washer)

PROS: Instant results, no harmful chemicals, no specialized equipment, 1 man job
CONS: Getting on roof, Permanently damages roof, basically stupid

Method 2: Medium Pressure (Shampoo, Steam)

PROS: Instant results, less harmful chemicals
CONS: Getting on roof, Permanently damages roof - but not as bad as high pressure

Method 3: Low Pressure (Bleach)

PROS: Mostly Instant results, recommended by manufacturers, getting on roof is optional
CONS: Some pressure or scrubbing may be required for moss

Method 4: Zero Pressure + Time (Isopropyl alcohol, potassium soap of fatty acids)

PROS: Safest method, no getting on roof, one man job
CONS: No instant results

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Ok, you sound like a pro with roof cleaning. @florida_condo_cleani is missing out on roof cleaning work because of heavy rain. Are any of those 4 options doable regardless of weather?

Anyone use peroxide?

Pfft. I’m just trying to wrap my own brain around it. I wouldn’t want to go up on the ladder if it’s raining that hard.

Somebody had a video of a roof they did with percarbonate. Small commercial property… I can’t find it. I’d put that in the Zero Pressure + time category. It takes months to see full results.

Hey. So ive been cleaning alot of roofs lately. I always have trouble with clay barrel tiles. It seems like nothing but pressure will clean these things. Have you tried all the methods that you listed? Whats you’re go to for clay barrels? I did a roof today that reassured me that there was no way to possibly soft wash a clay tile roof. All the allgae on the North side of the house was already dead from I’ve exposure. It would rub off with my finger or a brush (if I put in some serious scrubbing) but it would absolutely not rinse off. I had to hit it with medium pressure. At this point I’m not cleaning any roofs clay tile roofd that I cant walk. The $ is still good bit it’s a little frustrating reading about guys who just spray and rinse. I can do that with asphalt and cement tiles but clay barrels are a different animal.

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As of now my approach is to hit it with a 50-70% mix( I test with a pump sprayer first) then go and “softly” blast off the remaining lichen/ algae/ whatever it is. Buy the stuff definitely doesnt just rinse off like it does with asphalt or cement.

I’ve tried everything except steam. I can’t help you with the clay barrels, though. Nobody has them. 99% asphalt with a sprinkling of slate.

Pretty much every lead for roofs that come in lately is clay tiles. There’s alot of them in my area. Mostly upper class homes which is ideal because they can afford to pay what I want to do such a chore. I just thought it would be easier. That being said…with the method I put up earlier I cleaned a roof In 3 hours for 1239. Thats more than I make hourly doing anything else so I’m going to keep doing it.

I love the money but the work is iffy. Basically all the info here about cleaning roofs doesn’t appIy to the roofs ive been coming across. I thought that the wheel already existed but here I am re-inventing it. Ive got a few more coming up. I’m going to try some sodium hydroxide on a small section next time and see if it makes a difference. I’d love to find someone to sub these jobs out too. According to what other people are getting $/psf I’m about double. Somewhere between .40-50 psf. I started quoting them high prices because didn’t really want to do them and then people started accepting my price so at this point I have to figure it out. Even if its safety harnesses, etc…

Edit: I did use hot water and noticed a significant difference.

Those clay tile roofs and barrel roofs are dangerous. When you add SH to it it’s like walking on snot. But yeah got to have pressure for those. Those can be painted as well and i get $3.00 sq ft.

$1239??? The average roof cleaning price down here in FL (in my area, anyway) is around $300 - $400 and that’s for barrel tile. I wish I could charge northern prices.

Looks at the picture it looks just like some of the roofs I see here mainly ones that haven’t been cleaned in a long time or at all. They can be stubborn. In the picture it looks like one side of the tile is worse than the other . That typical of algae and that’s likely the north facing side of the tile. My suggestion is first don’t rince it off. Second I don’t think you chem is worth a crap. When I run it to that crap I retreat the area every few minutes sometimes 5 or 6 times before it starts to go away. It’s sounds like overkill to keep hitting it before letting each coat dry but its what I’ve found that works.

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Yes roofs are much less down here but don’t forget. We work year round. There is probably 10 times the amount of roof cleaning work to be had here than up north. Our chem is $1 a gallon there’s can be up to 4 or 5 a gallon in some places . We don’t deal with much linch. You usually don’t have to educate customers on how and why. Hoa’s Send letters telling them to get it done. The type of algae we deal with in Florida especially the further south you go cleans up quicker than up north. The wormer temp of the roofs also assist in Cleaning the roof when the SH is applied. And just simply the amount of time it takes to clean a roof in FL vs other areas is much less. When you really consider everything we get about the same PROFIT per hour here as that do up north.

Your rates are low I work all over FL and I meal all over. You should be charging $400 minimum on tile roofs and averaging over $500 since most homes built in the last 7-10 years are typically 3000sqft or more

Yeah that roofs never been cleaned. Every roof ive ever done is a first time clean. Its not as common here as in Florida. I have a theory that the dry climate in my area is what makes it so difficult. Its never fresh green mildew. Always caked on and dry. I would rather not rinse but then the roofs still dirty when I’m done. That picture is half cleaned…kinda. What I did there is remove all the baked on crud first then hit it with roof mix so I wouldnt have to worry about slipping. The right side is after pressure cleaning but before post treating.

I’m in coastal southern California. I used to be alot cheaper but seeing as how I have to walk the roofs to get them clean I raised my prices. If I was going to get half that I just wouldn’t clean roofs. Its not worth the risk to me. Asphalt and cement I’m usually between 20-35 cents psf.

Watch your language lol feels like I’m back in elementary school people are way too PC serious question has anyone ever had a single customer from the forum?

Spray the roof once…spray bad areas twice and don’t rinse. for barell tile roofs bump up your mix close to 50/50

Explain to customer that over the next 30 days after a few rains the roof will be clean. If not we will come out and rinse it. Give NET 30 on invoice.

I give net 30 on all my roofs…customer is not so concerned about the roof looking dirty when your done if they aren’t paying you on the spot.

I try and schedule my roofs together in a 2-3 days in a row. I did 5 roofs 3 weeks ago and it hasn’t really rained until two days ago. Yesterday all 5 customers paid and said “roof looks great”.

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Watch the language. Please edit

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Thanks for the advice. But if I can’t rinse the stains off I don’t see how the rains going to do it. The other main issue is that it might not rain for months. Not a real rain anyways, especially this time of year. I did a roof a month or two, I ended up not charging the guy because it wasn’t up to my standards. We called a few days later and he wanted to pay us at least something because it looked much better but in my mind it wasn’t “clean.” Ill follow up with him on Monday and see if its looking any better. If it is then I’ll start doing net 30… Except for a small deposit.

You’re probably right. Truth be told, I’m not a very good salesperson and I tend to underbid all around.

It’s a learning process for most of us