Why NOT to apply Metal Roof Coatings - The worst thing to ever do 

Multiple issues here. 1) Never mentions how old the acrylic roof is. Acrylic coatings tend to lose 1-2 mils of thickness per year due to weathering which is why most manufacturers offering 10 years or more for warranty purposes require at least 2 coats. Better products with higher acrylic solids perform better and offer more flexibility and this coating from visual observations doesn't appear to have had such high solid concentrations. This roof appears to be at least 15 years old or more given how brittle the coating was, but he doesn't mention the age of the coating once. 2) Obvious to anyone who has been on hundreds of metal roofs that were coated with either acrylic or silicone, this roof was prepared poorly for the coating application. As with any paint or coating, preparation is everything if you want it to stick. He scrapes and wire brushes the metal roof and never bothers to clean the dust off or wipe the area he is working on before applying the product. So now a majority of his wonderful repair and product is adhered to dust on the metal panel area from wire brushing. 3) Metal roofs tend to have a lot of expansion and contraction, so as the original coating becomes more brittle there will obviously be cracks and fissures forming on the coating surface. 4) He runs panhead fasteners into the pan of the panel, not the best place for fasteners without an EPDM grommet on the fastener. Given the force he applied while driving the fasteners, my guess would be all the fasteners he installed were overdriven and will eventually begin to back out due to expansion, contraction and being overdriven. 5) He has applied his product which is relatively thick and has basically created a coating seam that is bucking water on the uphill side of the repair. Constant rains will eventually work its way under the repair given the area was prepared so poorly over time creating the same issues he is highlighting. 6) Did he bother to check if the rusted fasteners utilized were even compatible with the metal panel. Often times, contractors fail to realize some fasteners they use during repairs are not compatible with certain metals and this accelerates rusting issues between the fastener and the panel. The entire thought process that coatings are bad for metal roofs when in fact you are applying a coating yourself is ridiculous at best. As someone who has served as expert witness in multiple litigation cases on issues revolving around roof system installations, I can state I have seen extremely good coating applications and have in fact represented some in court that were not so good. A majority of the issues revolved around poor preparation with maybe 1-2% of my investigations involving around issues with the product itself. With any coatings, choosing the right coating and thorough preparation of the substrate either provides a long term solution or a short term nightmare. Bottom line, do your homework and understand the most expensive coating isn't always the best. All in all, if this was meant as a positive promotion for their product, it was done poorly at best.

I used Kool Seal roof coating on metal roofs on mobile homes in Florida for years and never had a problem. The old silver coating and the white coating too.

preparations makes the job. good video

Liquid application on Metal Roofs are actually a great option . This coating problem he is talking about us a combination of cheap coating ,bad surface prep and poor application .

Not a fan of elastomerics but for some roofs that don't really need to extend their service life i guess it is an OK fix. Our roofing company has used pretty much everything out there over the last 25 years. We use only one products after 8 years of success and not callbacks. There is a Liquid butyl rubber made by epdmcoatings. What we like about it is that it does not need a primer for any of the roof types we have applied it over that goes for metal, BUR, epdm, foam but NOT silicone. also it is a one coat application so we close much more business with this product because we come in as the lowest bid! It is a solvent product so primarily the reason it last all the years. Cheers

Any advice for removing rust on large scale for a big roof like in your video? I saw people use acids

'''''''''''''''''''''''You're the best teacher! Thank you so much

I am from Chennai, India. You really saved me. I was about to buy the "So-called metal roof heat insulation coating". I might have ended with the rusty roof!

I'm glad I found this video. I have a leaking metal roof and was considering a coating. Now I know better.

Thank you for the video Roof Doctor!

Great video..one question, on an R-panel roof if it looks somewhat bend in or stepped on hard..like someone stepped on it very hard and now it looks like bend downwards and to the sides where it was stepped on....will this case the R-panel to leak?

Too good sir respect for you from India

Roof Doctor, I have an older metal roof that has begun to leak. It was put on with roofing nails. The gaskets are old and some of the nails have begun to back out. How would you suggest I repair it. Replace all the nails with larger screws or..? And seal the seams?

Our 30 year old ministorage has 30k sq ft of 29ga galv or galvalum on 5 of 6 buildings. Similar product as your video but never painted. Purlins are 1x3 wood spaced too wide at 36"-42" on factory wood trusses 3/12 slope. Concrete block sidewalls. New gutters and downspouts. In our 3 years have learned that NOBODY goes on the roof except a personally trained worker. Fortunately we identified dents which allowed gaps in the overlap seams (from 30 years of untrained roof-walkers) and have sucked them together with rubber-grommeted screws on top of the metal profiles. Replaced probably 25% of the suspect screws with larger diameter (75% yet to go) Appears leak problems are NOT accelerating, original fastenings mostly without rust stain (thanks to galvalum corrosion protection & rubber isolation washers). We've made significant gains against the very few customer complaints of water. Was a risky investment! BUT the facility is below road-level such that the roofs present a poor image of our business and brand. Multicolor stains over white oxidized alum as you would expect. Unthinking, I thot to paint to achieve unform color, prhps white for heat control. But I know it will get dirty. THANKS for the headsup about coating. But what shall I do for COSMETIC? And how to invest in a long-life impermeable roof? I'm thinking to add z-metal purlins on top of existing roof, one above each 1x3, plus one between, then a new powder coated roof over top. This way 190 tenants aren't exposed during the project. And prhps we insulate the space between old and new roof. How can I reach you as a consultant?

Jetcoat and Henry Extreme sprayed on with a Graco Pro in three layers would work just fine in MOST applications. White is not very reflective compared to dedicated reflective coatings folks. Use your resources folks. NOT angry contractors fixing crappy jobs after the fact. Bad prep is the key of this video along with climate and weather in regions

Thank you so much!!! I learned so much watching your video!! Great education for us metal roof newbies!!

Acrylic coatings are great for metal roofs. Like you mentioned in your videos, it's all about preparation. They obviously didn't prep this one. In California some contractors use a seam tape that has a peel and stick backing and polyester surface. Once that's installed over seams and voids we apply acrylic gel and then after it's cured we apply lMetacrylics coating. That particular Astec didn't fare too well in Ca. Too much ceramic in the formula and lots of what you see there. I enjoy your videos 👍🏽. Keep them coming.

I have a question. I have a very nice mobile home. I have a metal roof. Every time it rains or the wind blows I have this grey matter that lands on my deck. To me, it looks like grey silver sealant or something. Any idea what I would replace it with?

That seal will last 3 years tops, if that. Not to mention it was applied over an apparent wet and very cold surface which means adhesion is minimum. This will dry, crack and peel very fast. Also, the black color will take a beating from UV rays that will further accelerate deterioration. I'd love to see the state of this patch currently as this video is now 3 years old.

My zinc awning has rusted very quickly without a coating, so how do you stop the rust if not with a coating?

Can someone tell me if they wanted to change the color of their metal roof could they do that? What product / preparation would they use?

Does turbo poly seal dry hard or does it stay tacky 🤔

Preparation is essential and proper application is important. However, using an acrylic elastomeric that doesn't lose key characteristics, like essential flexibility (elongation), is key to a superior roof coating. Most roof coatings on the market will use inexpensive plasticizers (for flexibility), which leech out, and cause eventual cracking and/or flaking. Same thing happens with asphaltic based products (i..e aluminum asphalt), as their oils will leech out of their coating. Acrymax's acrylic elastomeric won't lose their flexibility as it is built into the backbone of the very polymer (of their resin). This allows Acrymax coated roofs to have their life extended almost indefinitely with simple periodic recoats (at 5, 10, 15, or even 20 year intervals). Recoats simply maintain mil thickness. The thicker, the more robust, the longer before a recoat. See this video link, highlighting a college's roofs, done with Acrymax nearly 40 years ago and still going strong today: ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-Q2m8rHBIUVg.html

I have been coating roofs for 21 years and I agree with everything you have said . What I like to do is use Polly seal and then coat with asphalt aluminum ,just because asphalt aluminum makes it look nice and you can't see all of the patches and because it is a very thin coating ,asphalt based coating it wears away and doesn't peal but it must be non fiber . Any silicone, acrylic or elastomeric I have ever used has failed horribly within 5 years and would have been better off to not do at all. Also asphalt aluminum does great on rusty areas ,I have coated roofs that have been on over 18 years it doesn't stop leaks but it wasn't designed for that but it makes a nice top coat.

Yep. I spent over 1000 on 3 cans of rubbet coating and found out water trapped under and rusting metal away.

I'm getting a snap-lock standing seam metal roof installed on my house. Would recommend that I get bare (unpainted & without acrylic coating) AZ55 Galvalume steel panels, instead of the more common acrylic coated or painted steel panels?

At 10:45 you say, "acrylic, all silicon coatings I don't think works" & then repair with Turbo Poly Seal, but list Super Silicon Seal as your best advise in your Summary text - which of the two products do you prefer?

So what do you suggest to coat a metal roof? I don't have a leak but my metal roof is in need of a coating in general and I typically hire someone to do it and they put on a Kool Coat in double layers.

thank you

What do you Recommend for painting Polycarbonate Plastic Roofing Material??

👍👍👍 like ur videos it’s a good advice in what brand to buy and what not

Sir, many thanks for this excellent video! What do you think of Geocel brush on product? I have been using Geocel on RV seams and chimney flashing. This Poly Seal looks like an awesome product.

What do you think about polyurea coating on metal roof?

Nice!! Thank you sir

Interesting topic. I plan to paint my roof with a white acrylic paint like that. There is a difference though. I see that you had ice underneath the paint. My house is in the tropics where I NEVER have ice formation. I think the melting and freezing of ice (which causes expansion) is a major cause for the paint to be pulled off the roof. Even if it would affect the durability of my roof, it's probably worth it painting my roof, because of the aircon energy I can save from painting it white. I do have a lot of expansion and contraction from the hot sun, but perhaps the white paint can help to reduce that expansion a bit.

Is a granulated roof the same as a modified bitumen roof? If not, which roof is better and why? Which one last longer?

For a guy who do the job and understand by heart is someone to believe NOT just any expert BS.

Hi there, thais for the good video. I have here a 60,000 water tank with rusty big patches inside of it, and I saw today little drops coming from the outside. Help, how to patch this up? Could I use your technic, I also have been thinking of cement with water proofer but then I have to do the whole tank, it looked like a cold long day on that roof. Greetings from southern Spain.

At 9.15 when you screw the sheets together and water comes out. Can this be due to condensation running down underneath the top sheet into the lap? Sealing the top surface of the joint keeps this water in. There is a reason why you should probably leave the lower edge of the lap joint open to drain. The alternative is to seal the top and the bottom of the overlap to keep the condensation out, making sure you use screws with washers to ensure the water tightness there as well.

What can I used to those covers then

Ty kindly 🙏.. Northern California and two roof contractors messing around. Can you come here....6/22

It depends too on who installs it. I worked for one roofing company that had put put on the coating that needed 16 hours minimum dry weather and we slapped in on 2 hours before the rain came.

Great information on metal roofing. I have a question and would greatly like your professional opinion. What do you recommend for a metal roof that has some surface rust that is not deep, but needs to be coated with something? Thank you very much!

There it’s a wrong coat. The good surface preparation and right paint it’s going to extend the roof life a lot.

In actuality, the problem is way more complex than what he's making it sound. It could have been a cheap coating. It could have been poor Surface Prep. We have no idea how old the coating was in the first place. It's very important to recoat your roof when it's necessary, not when you have leaks. It's also important to use a rust inhibiting primer underneath your top coat and seal off your Fasteners with caulk. His logic is very over simplified.

can you put the turbo poly seal over existing tar & flashing?

I have a Galvalume roof and would never just slap an elastomeric coating on it without surface prep. I would first spray it with a bleach solution to kill mold and bacteria, rinse, and then make a dop stick by stuffing an old athletic sock inside another one and zip-tying it to the end of a screw-type wooden rake replacement handle. I would get a gallon of Ospho rust converter and saturate the dop stick and dop each screw, twisting the stick to get thorough coverage. I also would seek out any rust (generally not a problem unless you let the roof go way too long before taking action). I would then use aluminized fibered roof coating to cover each screw and seam before applying elastomeric coating. I would then wait several days until the coating had cured and then apply two coats of elastomeric coating, letting the first coat dry thoroughly.

Sooooo what do you to do a metal roof that's coating has worn off over time then? You can't just leave it uncoated or cover the entire roof with that poly seal stuff.

What to used to bprotect the roof galavanae

What's the best way to clean a Mobile Home metal roof? I live in a co-op and they are pretty fussy on how things look around here. I was thinking about coating my roof, not anymore....thanks for the education!

Your teachings are very good. Thank you.

Question - I brought a farm 4 years ago and the barn has a shingle roof on it. Problem is that who put it on put the shingles on plywood over a metal roof. Currently "cleaning" off the shingles but have alot of holes. Any recommendations?

I want use flex seal max for my patio roof that is metal..what do you think of that.??

It's called washing very well and priming all your bolts and edges then coming through and spraying it correctly alot of painters don't know the proper way to spray always spray your corners and edges first similar to cutting in maybe 3 panels then come back and spray your face surface I've sprayed many metal roofs and never got a call back it's all about taking your time and taking pride for your customers

Dankie Oom. Lekker bly.

Havnt you applied the asphalt aluminum coating before? I thought you liked that stuff

Excellent video!!! Would small pieces of fleece and poly seal be good for screws that are leaking? I have replaced the dumb grommet screws with new ones and it didn't solve the problem so I wondered about doing this on them. Thanks!!!!

I have been coating roofs for 20 years . The best way to coat a roof is to, patch all nail heads with through the roof / geocel. And coat roof with asphalt aluminum non fibered . Asphalt aluminum wears off and never peels , all silicone and acrylic will eventually let lose over time and then you have a mess. Also asphalt alum is a rust inhibitive roof coating . This man knows what he is talking about

Thanks a lot. You have saved my hard-earned $$$. You are a good man!

The metal roof on my garage is over 50 years old. Has original coating. No holes no leaks. Leaving it alone

Wouldn't roofing screws be best option for safety on steal roofs? Depending on pitch I guess. Regarding this video I'd prefer raised hex screws for safety. Keep in mind i know minimal about roofing

Enduris coating has served me well.

I am wondering if it will work on my RV roof.

Just like some of the under coatings sprayed under cars on the frame. Some just trap the water & salt causing it to rot out faster.

I would highly recommend going back with the same type of screws it’s not very practical to use anything else on a roof

Im apply primer coating Idont have problem like this .now my point is roof coating is not for ever

A lot of my friends that live out there tell me I should move out there because I'll make them Fortune and that's a lot easier but all the red tape then it is here in Chicago it's also good to have friends out there

What about 3 course on the seams and using silicone based coatings?

CI Roofing I Have to agree and Disagree with your opinion We have Sprayed over 700,000 sft so far in 2020 of Acrylic on Metal Roofs and don't have that issue At the end of the day its all about proper preparation and cleaning Theres is a lot of flyby night shady roofers out there So I feel you not being partial to the product that Hundreds of vendors sell the Acrylic The application you have applied is the basic Roof cement that I totally despise that makes by Coating look bad after it dries because it shows thru I respect your view But I still trust Acrylics if applied correct

And whats the black stuff you put??

Is there anything you can put on metal roofing or basically just leave it natural the way you buy it would anybody happen know

Poor guys freezing up there. He needs a work blanket & pillow 🤣😂😆

This Guy is Amazing. I cant imagine the idiots who put the coating on it and how the owners were looking for a Man who Knows His STUFF!

Absolutely! I see the eyes

Was looking to use a product like this on the roof of my ol suburban. Silicon then?

That’s a lot of work !

LOVE YOUR VIDEOS. ARE YOU SOUTH AFRICAN? DEFINATELY HAVE THE ACCENT. SO IF YOU DONT RECOMMEND ACRYLIC PAINT WHAT PAINT IS BEST FOR ZINC ROOFS? COMMENTING FROM SOUTH AFRICA

The main purpose of those white color roof coatings is to reflect the solar heat. Without the coating, the roof would get unbearably hot, and heat up the space beneath. I'm glad that you show this problem, but not painting is not a good solution either. There should be a better solution.

Hi flat dr EPDM install 6 years what is best roof sealant for EPDM thank you.

im new to metal roofs just bought a house with one and its a bit rusty. i dont have regular paint on it only the silver metal. what your talking about is someone painting the roof a color right? your not talking about elastic or fibered aluminum coating right? because i have some surface rust and im almost positive i need it brushed off and recoated with one of the 2. this house is 100 yrs old

Sold in 5 gal?

Roof was not cleaned properly before wrong acrylic coating was installed. Should have used silicone. Best to fill flutes and install a TPO membrane roof using the Rino Bond method of attachment.

Where can I buy the poly seal from?

I have a metal roof about 40 years old, the nails are not working anymore and I need to install screws, what would you recommend? A screw with a rubber gasket? THanks

Roof coatings are great and much less than a brand new metal roof. You have to clean, prime & install the coating properly. Some manufacturers make rust inhibitor primer. Also temp and moisture makes a difference. Gaco makes a great product. Only one I would use. Silicone!!!!

Is liquid rubber as good as turbo polyseal?

I would have chemically treat the rust first to neutralize it. Grinding off thick rust and covering it up just looks good. The rust remains and grows again. IT is a band aid that looks good. The rust remains.

We love coating metal roofs 😊 Love your videos though!

What do you to on a 30 year old metal roof that the original coating is starting to degrade? Change out the roof? It is a very high end metal design.

Silicone coating fits dry and hot areas more since it’s UV resistant

I think I would have brought the poly up over the sides

I can promise you it wont last forever it will leak after a long time but does work better then other products

RIP that man

Prep is a job in itself. My opinion is that the first step wasn't done property and that is sanding cleaning brushing away blowing etc.

It's why people use FLEX SEAL(WHITE) to seal the whole roof at least 3 full coatings. NOT little bit here and there because it will cause that problem. You must cover the whole roof. 3 coatings will do it and last for decades. It cost a little more and saves you big trouble if done right.

i have 900mt of metal roof and that black thing with time sun burs it and it turs like dust,,i clean everything and use a 20 year warranty silicon coating and its 6 years now and in perfect condition

I agree you can’t coat every metal roof. Some are just too far gone, you either need a super aggressive primer $$$$$ or tear off.

Can you tell me how to replace a skylights on a metal roof that is 50 years old? I cannot find a pattern that matches the old metal roof

I have a leaking roof in Louisiana I'd like you to look at....any chance you're coming this way? LOL

Peace… Shalom… Salam... Namaste and Thank You so much for All that you are doing to Heal our Mother Earth 🙏🏻 😊 🌈 ✌ 🌷 ❤