The HOTTEST Roof Might Surprise You - Metal Roof vs. Asphalt Shingles
ฝัง
- เผยแพร่เมื่อ 14 ต.ค. 2024
- Thanks to Metal Roofing Alliance for sponsoring.
www.metalroofi...
Subscribe and follow my Podcast on Apple or Spotify!
Apple: apple.co/32AOwgU
Spotify: spoti.fi/3FXNg4X
Sign up for our twice-weekly newsletter:
buildshownetwo...
To sponsor a video or advertise with us visit:
www.buildprodu...
Want to learn more about building? thebuildshow.com/
The Build Show on Instagram: / thebuildshow
Huge thanks to our Show sponsors Builders FirstSource, Polyguard, Huber, Rockwool & Viewrail for helping to make these videos possible! These are all trusted companies that Matt has worked with for years and trusts their products in the homes he builds. We would highly encourage you to check out their websites for more info.
www.bldr.com/
polyguard.com/
www.Huberwood.com
www.Viewrail.com
www.Rockwool.com
![โรงเรียนดัดสันดาน นักเรียนเถื่อน..!! [โรงเรียนไดเม่]](http://i.ytimg.com/vi/vRKPeXn4Fl4/mqdefault.jpg)
An alternative to these 'high performance' roofing materials is what we here in Oz call a 'Queensland roof' or 'tropical roof' (which i'm sure is not unique to Australia, that's just what I know them as ). It's simply a sheet of normal metal roofing material (CustomOrb or whatever), then a spacer, then another sheet. This creates an air gap so ambient temp air can flow between the sheets and carry away the higher-than-ambient air from the underside of the top sheet before it radiates onto the lower sheet.
I always kind of wondered why this wasnt more common. Best I could come up with was cost, but it seems like it would be vastly superior in performance
yes, but it needs to vented, to draw in air from the soffit and vent the hot air through the ridge vent. This is how I have my roof constructed (in US).
Hindsight is 2020. Feel the Bern 😂❤
Add insulation between the roofing material and the deck for a retest. Also radiant barrier decking. It’s all about heat transfer into the structure.
Heat absorption from the top most roofing material is what matters most in sunny weather, which is what he's measuring.
All starts with how much heat the top of the roof absorbs, which is what this is about.
Asphalt has cool roof technologies that weren't used. Try testing the newer roofs with a radiant barrier. Just the fact that the show was sponsored by the metal roof manufacturer made me want to run. Like the Tabasco industry funding a study that says smoking is safe.
Also, as per one of his previous videos, most attics have insulation and such on the ceiling rafters, not the roof.
Nobody with even a modicum of construction knowledge places insulation between roof deck and the covering. That’s where the airgap is for convective cooling/ventilation.
We always have an air/ventilation gap between deck surface or between roofing deck and insulation stacked atop rafter decking as we do hear in CO and most colder climates.
I have painted both metal and shingle roofs white and it cuts the heat transfer dramatically. Unfortunately the white paint tends to grow stuff like the bark on an oak tree. Overall the best is metal that was painted white at the factory.
It is often recommended to work best, place bifacial solar panels on a white-white surface for maximum reflectivity.
@@lunatik9696 yes, bifacial solar panels are the new rage, and costs have come down, however lots of solar experts question their best use on a roof mount array. Background needs to be reflective to be effective, and the roof rack for array has to be optimized angle to take advantage of bifacial panels. Flat mounting is not beneficial. Bifacial panels seem to be best in a vertical position mount such as a fence, deck guardrail railing, canopy, green house roof, etc.
The video shows off metal shingles with a coating that cuts down on heat transfer that works no matter what color it is. White and black have no difference due to the coating which does the the reflecting, not the color.
Interesting video! Our situation was a 10/12 pitch roof, asphalt shingle getting older, no leaks but some hail damage. No one wanted to climb up and reroof for us. So we had a steel roof installed, on top of the asphalt shingles, no tear off expense, and amazing results inside the attic and on our electric bills. Been up there for over 10 years, no problems! Lots of layers! Metal, asphalt, felt, and decking. Gable vents, and power vents.
A side note on white Henry Roof Coating. I did the same test using the Henry high solids white roof coating onto old black shingles. The result was over 30 degrees cooler roof temperature! The bad news is now 20 years later the coating is almost black from condensed dirt. It is VERY difficult to get this dirt off. Pressure washing is most effective but a lot of work on a 45 degree slant roof! (the roof coating is still solid and intact!)
I am VERY impressed that you took into account the IR thermometer's emissivity issues and compensated for it. Great video!
Matt, since everyone is complaining about the heat, and how hot their houses are, give us an update on how well your home is performing. Bonus points for sharing your electric usage
Grate Content, Matt.
You can make the metal roofing even more efficient by adding an air gap between the metal and the decking (vented over roof). When I had mine installed the attic was barely warmer than the ambient outside temperature. And that was before insulation. I like the way you approach the "show me" aspect :)
Everyone should do this in any case, to let moisture out.
You should be using thermocouples. Infrared can be tricky with different surfaces, especially emissivity. (Adding that the Flir and the IR gun essentially use the same technology).
The under deck and ambient temps are the best indicators. Although the metal is back like the asphalt, it has way more reflectance than asphalt.
These are essentially painted surfaces. There's almost no difference emissivity.
@@mitchellsteindler compared to the traditional asphalt shingle?
@KurtisSaiyo the majority of the surface is rocks coated in paint. So yeah it's all paint.
@@mitchellsteindler so I found this (digital.library.unt.edu/ark:/67531/metadc822838/m2/1/high_res_d/thesis.pdf), and you are correct. Emissivity of asphalt shingles is very close to paint. If these are not painted, but anodized, the emissivity would be much lower. Color makes no difference in emissivity, however it does in reflectivity. They also reference a 2002 FLIR publication that states that thermocouples are the most accurate way to measure surface temperature.
The shiny metal surface has low emissivity in both visible and infrared so doesn't absorb sunlight well and doesn't re-emit thermal infrared well. The black metal has intermediate emissivity in visible and good emissivity in infrared so absorbs some but not all sunlight energy and re-emits thermal infrared energy well so has similar temperature as shiny metal. The asphalt has high emissivity in both visible and infrared so absorbs the most energy but only re-emits about the same as the black metal. The best solution is paint that is white (non-absorbing) in visible sunlight and black (good emitter) in infrared. Almost all visibly white paints are good reflectors and most are pretty black in the infrared so are good emitters and so would be cooler than your samples. There are recently developed white paints that are very reflective in visible and excellent emitters (very black) in the infrared so on clear days (radiation to/from sky is better on clear days) they will be BELOW ambient temperature!
And some of those white coatings are available on current roofing materials, including both shingles and metal roofs.
Couldn’t have said it better, thank you for the nice breakdown of the science involved.
Don't forget there is a huge difference in mass of the two types of roofing material also.
Who makes/sells these new paints than can be below ambient?
Would have loved to see the cooling effect of solar panels on these. The air gap between the roof and panel would help with cooling.
As a gutter cleaner, can confirm. Asphalt is really hot even in the morning. Metal roofs cannot be walked on when wet though. Don't get a steel tiled roof. They have an asphalt texture. The tiles get bent and we can't walk on the roof to clean the gutter. We need to use a ladder the whole way around and it will cost you a lot because it will take us much longer.
Or just get screens installed and gutters won’t require cleaning?
K-guard or Leaf-guard gutters. Sorry to put you out a job :(
You shouldn't be walking on asphalt shingle roofs to clean gutters anyways, walking on asphalt shingles damages them.
@@clarkharms Then your screens get clogged and you just have to clean the screens instead.
@@bobbygetsbanned6049 maybe where you live, I am going on 10 years nothing in the gutters or screens.
I installed cheap 3 tab asphalt shingles on my house in 1988. They lasted until 2016. I'm on the south plains of West Texas where the weather is brutal and large hail is very common. I don't play the roofing insurance game like everyone does around here. It's a racket. I installed Malarkey's best shingle and canceled my insurance on my roof to save quite a bit.
When I had 50 year shingles installed State Farm lowered my insurance rates $600 a year.
I an going 17 years despite my neighbors. everyone had new roofs, especially after Nov 22 hail but across the street they are in roof 4. They had really nice redish 3D type and now, nearly black dark gray cheap ones. Like you said, after 15 years you are screwed basically.
@@greggcollins4215 same here. But slowly they kept raising my rates so I cancelled it. I'll invest the money I'm saving and build a home repair nest egg .
should have also done white asphalt shingles to compare to silver roof
Yes. That's what I wanted to see. Also a comparison of the white shingles to black. I got my house roofed with white shingles. I'm sure it helps, but I haven't seen my energy usage to cool drop noticeably.
@@danbert8 From years of experience I can tell you there will be a difference in longevity of the roof. A light colored roof no matter the material outlasts a dark colored material. That has everything to do with reflection. The metal roof will expand and contract far more than asphalt so it will make noise. Light metal makes less noise than dark metal.
Covered my barn and ranch house with white metal roofs...changed my AC performance drastically...1st time the AC quit running during the hot weather...house even cooled down..amazing.
A real world test would be taking the temperature of the attic in your own home with the ambient temperature outside to compare. So many variables but I believe you're right about the Kynar coatings on metal roofing. The one real world problem is cost compared to shingles. I know if you take the longevity of the metal roof against asphalt metal wins. But people want that immediate savings that shingles give you. I've put a lot of each kind on in my day and I really can't see why metal is so expensive these days. Especially when you have companies roll forming metal roofing right at the jobsite. I guess I'm just getting old... 😂
Obviously it depends upon your location and subsequent fire risk, but here in CO and much of Western states where wild fires are substantial annual occurrence, insurance savings for coverage on homes w/metal roofs can be significant. Obtaining insurance on home w/cedar shingle or shake roof is nearly impossible but many underwriters have also begun eliminating coverage for homes in certain heavily wooded regions, particularly for wood framed, wood sided and/or fiberglass shingled structures. We still mostly use wood framing and limited icf blocks but metal, stone & cement fiber siding, metal roofs, mineral wool insulation and full fire sprinkler coverage, including in exterior soffits. We also do not build any homes w/LPG or CNG plumbing or hookups. The result is more insurance coverage options for clients and lower premiums.
I had to shop around quite a bit to find the right metal outfit. My metal roofer brought shop-formed panels (not made onsite by a trailer unit). Bottom line: top quality metal (Kynar on Galvalume ) for just twice the cost of asphalt ($18K vs. $9K on my 1100 sq ft house). A lifetime roof versus one that will start to crumble in 10-15 years. Talk about a no-brainer, strictly from an economic perspective. Bonus: Never again will I subsidize pumping fossil oil from the ground to make roofing material; nor will I send a ton of asphalt waste to the landfill. And if the house is ever demolished, the metal is 100% recyclable. Win/win all the way.
@@MichaelM-to4sg I hear ya. Here in the mountains of southern CA we have very similar conditions with building and insurance. I am building a new home with all the necessary fire and seismic damage prevention, however, that doesn't seem to effect extraordinary insurance rates. I hate insurance companies. One of America's biggest rip-off's...
@@davidecasassa8679 You are entirely right on the quality of a kynar coated metal roof. The only fault with your comment I find is IF recyclable materials are actually recycled. I recently brought a load of recyclable materials from my new home build (ICF and cutoff framing material). When I got to the Waste Management landfill I explained what I had and was told to dump it in the landfill instead of the recycle site. I tried to insist on the material being recycled but was told I could take it back if I wanted or dump it in the landfill. I'm still pissed. We should all try to do better at protecting our environment. My point is that government and companies lie about recycling all the time. As a nation we probably do a lot better than many other countries, but we definitely could do better. And don't get me started on EV's... 🤣
@@dunep6465 Nonsense. Insurance companies rate their policies on their RISK of payout and have to include all sorts of risk factors = remembering that a house that has all those extra features costs more to replace when it is damaged so the savings is muted. The problem you have is that the two states with the largest number of home owner insurance claims are Florida and California - so insurance rates are higher there. When you add in the higher cost of construction in California - you get rates that are much higher than other states. (Texas is third) But living in California is your choice - and your risk. So you have to pay higher premiums.
I have a corrugated roof from 1955, and I recently coated it with white elastromeric roof coating, but I added a ceramic microsphere heat shielding additive. I would like to see some comparisons with that kind of technology. My building is much cooler now-
Asphalt shingles have an immense thermal mass. Which is why you can be uncomfortable all night as they reradiate heat from the day down into your house through the night.
That's a great point. I hadn't considered, fixing to get a matte black metal roof to replace my shingle roof. Would be interesting to see what the temperature of the two roofs would be after sunset a few hours later.
How about (clay) tile roofs? Also, there is white/light-grey shingle as well which might be interesting to compare.
This would be interesting to see.
Great job, Matt; I didn't expect you to check the temperatures properly; it is amazing how many mistakes people make that give them junk readings. I would have loved to see the difference between metal shingles and a ventilated standing seam roof.
It's a sponsored video, making us all better informed with unbiased info was never the intention.
@@TheAxecutioner I couldn't help but notice how prolific you are in selling this message. Is this your full-time job? Does it pay well?
@@davidecasassa8679 No pay, construction is my full time job & i couldn't care less about asphalt shingles vs aluminum shingles, but don't people deserve to know when they're being shown an informercial? I think so. Take care & LLAP
Great video. When you first started the test I was going to comment that you need to build a box behind the roof to test the interior temps, then you did it, awesome. I am sure you can use those rigs to do some further modifications and more tests. Maybe a test with different insulation types. BTW, how long were the rigs sitting in the sun for?
Black metal roof was just installed in our custom build house about a month ago & love, love it. Now that it’s very hot but inside is still normal temp not hot. Besides the temp of metal roof it looks more elegant 😀
Our home had wood shingles. After a hail storm totaled them we replaced them with a lightweight concrete shingle that looks like a wooden cedar shake. They’ve held up well, but even though they’re a similar color to the cedar shingles they definitely absorb more heat from the sun. Our ac has to work more than before.
Wood shingles (hand split shake or taper sawn) actually help cool the attic. Wood shingles breathe because there are gaps everywhere on the entire wood surface, as soon as it rains the shingles' wood fiber swells and the roof sheds water. Go inside a wood shingle roof attic and you'll see daylight streaming thru everywhere (if shingles were nailed to 1"x4" instead of plywood deck) streaming daylight equals streaming airflow. A cooler attic home is an easier home to cool. Just my observation over the years.
I'm impressed with the insulative properties of the asphalt roofing, comparing the difference of temperature between the outside roof surface and the underside of the roof. The flaw in this experiment is you did not include a white or lighter colored asphalt shingle.
Perfect timing as I'm researching metal roofs for my new home! Would be curious on how this impacts heat/cooling in the winter!
This video (commercial?) was sponsored by Metal Roofing
For a future test: Could the test be done with radiant barrier facing the ´attic´? Also could it be done with white asphalt shingles or light colored rolled asphalt?
A radiant barrier is only going to create a difference in the temperature transferred to the barrier. What's being measured here is the absorption of energy through the top most material. There shouldn't be a change in top most material for a test on a radiant barrier.
@@MegaWhiteBeaner A radiant barrier hung on the underside of the decking (with an air space) would reflect the emissivity of the wooden deck back towards the shingles or metal roofing and would allow for a cooler attic space.
This is a metal roof sponsored video
@@TheAxecutioner I very much agree.
I always enjoy your videos and learn from them.
This demonstration was very basic and made a very basic point.
Some commented here about one thing or another, but for me, I got the main/basic point.
Obviously, there is a lot more to be said and considered on roofing, which involves more than just choosing a particular roofing material.
Thank you for a good, basic demonstration regarding two different roofing materials.
I tried aluminum foil radiant barrier on the interior ceiling surface and it reduced the temp 30 F on metal Florida room roof.
Taken with IR gun.
After cutting holes in the back sides of the three roof assemblies, I was expecting to see a blower door test performed to confirm how tight the roof assemblies were constructed.
Thanks . Rresent Metal roofing of course is mounted on strapping over the existing roof. Airspace under metal.
Great test. I was thinking the backside should be tested and viola, you nailed it.
I’d like to see how it compares to normal corrugated barn steel
Excellent video!
I would like to add as a veteran solar expert that the best roofing to install if you ever anticipate getting solar is standing-seam metal roofing. That is the roofing that Matt has on his home.
Installing solar on any other metal roofing is difficult, and expensive. But standing-seam metal roofs are the easiest roofs onto which you may install solar. So easy in fact that you can do it yourself if you are willing to accept any risk of falling off the roof.
Additionally, if it was my house, and I was installing a new roof, I would paint the plywood sub-roofing with ceramic insulating paint before installing the roofing. It is expensive to buy at retail, but you can make it yourself with household ingredients.
the best thing to solve is - what temperature does the supporting deck get to.
- good you did that..
Once one puts a Ventilation channel (with reflective membrane) behind the superficial roof deck, does it matter, is the mador factor for many - cost, durability (weather resistance) leading to longevity of the roofing system. (Insulation, isolation and adequate HVAC setup is vital for interior comfort.)
I love your videos even though I have no business being watching them. I’m not a contractor or builder. I’m just a homeowner. I’d love to see you make a series for DIY upgrades. Something the average homeowner can do with their current house.
Excellent video.
Since you already have the setup can you do the same experiment at night?
I read that a roof can bee cooler than the ambient temperature at night via long Wave radiation. I would like to see if the colors made any difference.
Curious what cementious roof tile would be like, ie. slate, Spanish clay, flat concrete, etc
- or clay tile as is very common internationally.
These are even more dense than asphalt. They will stay hot for longer. If you sit on some, brick or concrete steps, they stay warm after the sun goes down. The material with less mass will cool off quicker.
I have open beam ceilings over half of my house in NorCal. The T&g 2x6 ceiling beams have no insulation, just tar paper and shakes on top. It had a heavy wood shake roof when I bought the place in 1984. In the 1990's I replaced it with 3 leaf composition shingles, cedar colored. The house was terrible hot all summer and freezing in the winter, much worse than the wooden shingles. In 2019, I had a 1-3/4'' layer of sprayed rigid polyurethane foam put on right over the leaky shingles. It cut my heating bill by 55% in the winter and in the summer, the attic rarely gets above 90 degrees F even on days when the air is 107F like yesterday. I have no AC unit. But as long as the house is closed up, it stays reasonably cool until evening. The strange part is that the gable fan very rarely turns on most days. It's set for 95F. On days hotter than 100F, I disable the gable fan as it sucks in hotter air from the gable vents and would run until evening. The roof has 2 layers of acrylic top coat with mineral granules embedded between coats. I walk on it regularly with no ill effects. It's also much quieter inside. I have ceiling fans to move air on very hot days. It was the best improvement that I made in the house in 39 years here. The central gas furnace of 160,000 BTU was replaced with an 85,000 unit. So far, so good. I like the results.
Would have liked to see a light grey asphalt shingle
I installed well over 10000 ft of black aluminum fence.
My country boy research is,the more horizontal a black metal surface is...the hotter it gets.
So a 3/12 will be hotter than a 10/12.
Lay 2 of the same product,1 vertical vs 1 horizontal in the sun and check the temperature.
Vertical you can barehand ,the horizontal will burn your hand.
So angle of the roof,airgap,insulation, and color of finish,and finish composition will all be factors.
I live in Ga,heat index has averaged 105 the last 2 weeks.
Would love to see the difference in the winter months up north
On an older house, the best ban for your buck to reduce the heat entering your living space is to add insulation in the ceiling to keep attic heat out. In my 80s home, I installed R50 in the attic after re-sealing the A/C ductwork and coating the joints with mastic and my A/C electric bill came down 65% and it only cost me $900 which I recovered in the first summer! Call your power company, many have a rebate program for updating your attic insulation and can offer a list of insulation companies that participate in their program.
4:15 Thank you! This was the reading I was most interested in.
We replaced our dual layer shingle roof with metal many years ago and have been thrilled with the benefits. One of the biggest differences between metal and shingle roofing is the thermal mass. A metal roof will cool off much faster than shingles which is VERY beneficial once the sun goes down. This demonstration would have been much more complete if you had been able to include the temperatures dropping once the sample roofs were no longer in the sun.
Alternative is a vented metal (or shingle roof which draws in air from the soffit and vents at the ridge cap. using passive convection to help remove heat away.
Hey Matt,
Would you consider a cold roof install under any of those roofing materials? Cold roof when there are two layers of decking separated by 1/2 inch furring strips to have the roof ventilation between the two layers. Thanks, Heiko
To confuse matters a bit, infrared wave length of light is what we feel as heat yet our eyes can't see it. So you can really play with the colours (do a degree) and have very similar results - if you have an excellent IR blocker.
Another factor; roofing mass. Metal is very low mass compared to asphalt so it will shed heat very fast. I'm in Phoenix with a sage green metal roof and with the sun near the horizon my metal roof is cool to the touch. Any kind of asphalt would probably still cause burns (too chicken to test....).
We have very poor insulation in the attic (very low slope with about 3-4 feet of room at the peak making it very difficult to get around up there) yet comparing our electric bill to neighbors we are paying a lot less. Sometimes half. And in the summer I'm running much cooler temps to boot.
I'd like to see you. Take the same props and insulate under the deck and see the difference. Would be interesting to see if spray foam under the sheathing creates a hotter roof.
You would void oe warranty by insulting directly under the roof deck of a fiberglass shingle roof. Not to mention the moisture/mold issues that would result. Needs a ventilation airgap between roofing material and the insulation layer
Would have like to have seen white asphalt shingles. Used those and had a remarkable change in attic temp and AC bills.
I noticed a big difference in the temperature of my house when solar panels were installed. I'm thinking metal roof with solar panels would be a win-win.
That is great that these roof coatings reflect the suns heat energy, but my concern would be how long those pigments in the paint will last under the scorching Florida sun. A lot of these metal roofs down here acquire mold and tree sap which would have some affect on the ability to reflect or absorb the suns rays. Maybe if you take those samples and put them somewhere where the sun, rain,trees will be able to interface with them over a longer period of time. That would be an interesting followup video. I am looking at replacing my Asphalt shingle roof with metal and I started researching the different options. I guess the next video would be regular metal roofing against the treated roofing. Great Video Matt!!
Thank You for this video! Especially pointing out that metal roof is ♻️RECYCLABLE vs asphalt- which ends up in a landfill 😢
It helped me decide to go with a black metal roof! Installation will be done next week!
💖🏡💖
Great video. Makes sense. metal is a very good conductor of heat but it also as a result disperses heat. It will gladly share the heat with air. Asphalt, well it loves to keep heat in. It doesn't like to share. Yes sliver reflects better than black, but it sounds like the coating might do a bit of radiant dispersion work. Btw, I'm considering an upgrade to my house here in TX. How's the metal material you have samples of do against hail damage? We're near Waco and yup, we got hammered a few weeks ago. Not much damage this time for me, but I bet the next hailstorm will bust up my asphalt roof real good and would want to go with either metal or that rubber material you talked about a couple of months ago. Your thoughts please.
Asphalt has cool roof technologies that weren't used. Try testing the newer roofs with a radiant barrier. Just the fact that the show was sponsored by the metal roof manufacturer made me want to run. Like the Tabasco industry funding a study that says smoking is safe.
I think the Tabasco industry would be more interested in proving that their sauce was hotter than the competition.
I think you meant the Tobacco industry would be interested in proving that smoking was not dangerous.
autocorrect s/b TOBACCO
Hi Matt, great video! You may not be aware that in Canada the National Building Code says that you can not build an unvented attic unless you can provide proof that a vented attic is "unnecessary or impossible to build" so if you are going to do a future video on metal roofs and wildfire risks please include some information on fire resistant attic vents like those made by Brandguard and Vulcan (I don’t remember the manufacturer but there are also metal ridge vents that you should use in place of standard plastic ones which can melt in a fire).
Lastly, in addition to the high temperature roofing underlayments, the metal roofing material and the vents, people should also consider metal or cement board fascia and soffit material, as well as using metal gutters which won’t melt in a fire like vinyl will.
You always advise conditions space so insulate and lets look at the back side. White is much more reflective than silver. There is a new white that is 90+% reflective.
Thank you so much for the measurements on the backside.
Metal will always have an advantage but its ALOT more expensive.For the budget minded a couple of cheap Solar vents on that asphault roof would put inside deck temps 25 degrees above ambient or roughly the same as a Metal roof.
I would love one or more videos on best practices for residential houses in fire-prone areas.
That is a well done test! thank you for that
Would love to see anodized aluminum tested as it's emissivity is outstanding across the color spectrum of options. Great info!
Would be interested in the same comparison with a white TPO roof.
Would be interesting to see the difference between vented and non-vented roof.
Had an old house in San Leon that didn’t have venting in the attic.
I vented the gables and the attic temperature dropped about 30 degrees.
This translated to a cooler house.
While my results weren’t scientifically tested or recorded, it was a felt difference.
We had been baking with the air conditioning on in an area that rarely saw temperatures above 93 degrees and usually had a breeze year round.
While a variety of factors plagued the situation, it went from unbearable to almost comfortable.
@@helidude3502 thanks for you reply.
Additionally:
Which metal is best to avoid adding to the heat island effect? Silver or black?
What about plain, unpainted galvalume etc.?
Rethinking the black company shirts?
Cool vid. Informative, concise, practical results.
While temperatures are an indicator of heat transfer, it is not exactly the same.
I always think of temperature as heat density and BTU as energy density.
Related in this case, but not the same.
The best relative measure of heat transfer is the inside deck temp. That provides s reference.
Since the boxes, more or less, are equal; the inside temp tells the story.
Good test. Seeing temps with spray foam on the back would be interesting.
From a Texas roofing hail damage perspective, over a 10 yr span here in north Texas, had to file 2 replacement claims for extensive hail damage… what are the durability characteristics of a metal roof - is it more able to withstand the impacts of large hail stones? What is the cost/durability rationale?
Metal would be a class 4 impact rated roof. It will also have a higher wind load rating than a asphalt shingle roof. There are shingle manufactures who produce class 4 shingles, but cost is very similar if the roof isn’t very complicated. Major issues I’ve seen with standing seam roofs is not all HOAs will allow them, and insurance companies like to use an aesthetic clause to get out of covering damage to them.
FWIW Years ago when I had my own contracting business in Austin, I started using "Space Beads" to coat the underside of roof decks with them. The one I took the time to measure, an attic still open to the lower floors, went from over 155F to under 120F with just one coat. No insulation and standard asphalt roof..
I tried doing a Google search for space beads and I'm having a hard time figuring out what you're referring to. Care to provide a link?
@@CopeBUILT i believe he is referring to spacer boards to separate the roof from decking.. Commonly done with metal roofing. Bead board.
@@LemonySnicket-EUC In other words, put down some lath stripping, to create an air gap...
I thought he was spraying some space agent insulation underneath the roof deck plywood lol
@@CopeBUILT yeah, exactly, we don't know for sure sometimes what people mean. Verbiage is not uniform across the country that's for sure.
Would have been cool to see bare metal, and a standard painted metal, in the comparison as well, just to see if the "special coatings" were making much more of a difference compared to the material difference of metal vs asphalt.
Thanks, Matt. Wish you had one more panel - galvalum. Also, wonder if gauge makes any difference. Zef
The asphalt is a heat sink (thicker, less conductive mass). It probably heated up slower and cools off slower. The metal transmits heat within the whole sheet (spreading heat to a shaded area, for example); asphalt does this very slowly and I’m guessing not nearly as far. The conductivity of metal also helps release the heat to the air (from mostly radiant to ambient), getting it closer to the air temps than the more solid materials. Maybe we should incorporate these differences into passive solar designs so we get the free heat in winter, and deflect and release it in summer according to roof orientation and local climate.
Simple paint reading on walls with different color paint. Between white and a dark blue, 15- 140, I painted the west wall of all my wood buildings white. Big difference
I think it'd be interesting to see how long each one of those roofing materials take to cool down after the sun is no longer beating on them.
The thermal mass between asphalt and metal is significant.
Great, great video. Thank you for your hard work.
b4 my 'hail proof' metal roof, I had the original wood shingles from the late 1920s & TWO layers of asphalt, worst part was after the sun set, The Heat would come into the inside of the house. Amazing how much Mass, is in my old wood house w/ only token insulation
I applied lanco super cool white to my Central Fl flat bitumen enclosed porch roof and left one hand sized area. You can now hold your hand on the painted surface for 5 seconds. The asphalt roof you need gloves for 1 second touch.
I used their ultra siliconizer on my garage roof, man what a difference. It seems to make the shingles more durable as well, a storm ripped off shingles from the uncoated house but the garage was good.
I believe the reason that the silver box was the same temperature as the black box was that the black box had an unexposed 95F wall (with air movement, while the silver box had two 120F walls with no air movement on the sides. If all three boxes were separated they would have shown a difference.
How does it hold up to hail. Here is Dallas area, we get whammed randomly with some huge freaking hail blowing in from the West. Can certain panels be replaced rather than a complete replacement? --once again great video..keep it up
In Australia the go to roof are concrete or terracotta tiles usually in a dark grey colour. Can you test these?
Same in Guam
-or Zincalume and Grey colorbond custom orb
I live in SW Florida and every year in March I paint my roof with white sealant after giving it a thorough cloroxing. The roof is a bit hot to my bare feet as I clean it, it becomes pretty comfortable while I'm painting it and actually feels cool after painting as I walk around checking for cracks and missed spots.
I have severe arthritis so Air Conditioning is out of the question. Without the white roof summers here would be unlivable.
Oh yeah, sunglasses and sun protection is a definite must! Even with very good sunglasses I still get a mild case of snowblindness lol
No surprise here, I was applying silver coatings 10 years before the white became available. Properly venting the area between the roof deck and the interior ceiling insulation makes a huge difference also.
A video about wildfire prevention would be amazing!
I'll guess metal performs better due to air gaps between the metal and the underlayment. The asphalt probably transmits all of the heat right into the underlayment.
Would have been interesting to see white metal and white asphalt as well. From what I've heard from lighting engineers, white reflects light better than silver or even mirrors (so I presume it also keeps surfaces cooler).
How well does metal handle hail?
Another possible benefit of metal: ease of installation, if the roof is a simple design.
One quibble, Matt: you accept this wasn't a lab test, it was a "backyard" test, but then you said it was "proof" of how it works. That's too much certainty for a backyard test.
As a retired lumber yard assistant manager & retired Volunteer Fire Captain, I can tell you that the metal roofs are far superior to asphalt shingles for all the right reasons! Embers from a wild fire will fall off a metal roof with little to no damage; however if the structure is on fire from another entry point, metal roofs on a structure that is on fire, can be a nightmare for the average fire department! It takes specialized tools like a portable cutoff saw with special blades to cut the steel panels; however if an asphalt shingled roof, regardless of manufacture is near a wildland fire & embers fall on the asphalt shingles, the fire can spread fast on a hot & windy day & totally engulf an asphalt shingled roof! & asphalt shingles are extremely tough to put out once they start burning & the smoke is unbearable even with an airpack on.I recently put a metal roof on my elderly uncles house & then he coated it with a name brand white silicone coating & not only is the old house cooler,but it wasnt damaged during a severe hail storm! If I was going to do a flammability test on your test structure; I would just use a propane torch like the plumbers use,but I would have the local Fire department on standby,because like I said those asphalt shingles can burn rapidly & create a lot of smoke!
I have a white cement barrel tile with 1-3" space off underlayment in FL, bet it may hv been 110-115F next to others, but even cooler roof deck...I layed each tile 25 years ago, and underlayment I used should last 60.
Keep it going, would you also test concrete, tile, slate & rubber?
good idea! concrete, slate, spanish terracotta, and those recycled tire shingles he did a video on
Would love to see plain corrugated galvanized roofing tested. This is one of the most common type of roofing here in the Philippines. Tia.
Matt if you had that metal on slats and a continuous Ridge and a continuous soffit vent you can keep the attic ambient heat to the outside
We tried to get roofing contractors to bid a metal roof for our home last summer 2022 in the central Texas area, and they would not even give us a bid due to the high cost of metal roofing right now. So we ended up with asphalt. It is what it is.
Who has dark asphalt shingles? Please test what we have white, silver, sandy.
great test.what are the up front costs for metal tool compare to asphalt roofing
Would be interesting to use that barium-based, white reflecting paint on the asphalt.
I would love to see a test like this to see what the temperature difference is inside with different roof construction and insulation types is. Likely use the same roof material for wether that be metal roof or asphalt shingle. What differences could you have with say a SIP roof vs a spray foam vs batt insulations?
You also needed to test light colored asphalt shingles to make the test more complete. You will find the light colored shingles will also be cooler than the dark. It won't be as cool as the metal but this might show the heat difference in materials is not just color but additionally mass. Having done years of roofing I know that a light colored roof lasts much longer than a dark colored roof. That would be because of the reflective differences for both heat and cold. A light colored metal roof will make less noise from expansion and contraction than a dark metal roof. No mater which type of roof you choose, asphalt, metal, or other, the light color roof will be the best bargain in the long run.
How would reflective sheathing impact the asphalt roof?
I’d love to see how bright white compares
I'm so glad you measured in several different ways. The first FLIR measurement on the surface of the roofs is misleading. What matters is how much heat permeates through the roof before it would hit any insulation. It is possible for a roof to be hotter on the outside than another roof type but still cooler on the inside of the roof. So many metrics to consider, thermal conductivity across the roof surface, reflection coefficient, thermal resistance through the roof from outside to inside, etc.
By taking several measurements with different instruments, even if dollar store thermometers, you at least cover your bases. Thanks for the great videos, even if a lot of it is sponsored videos.
"All Officers! Respond to man with a gun in Risinger parking lot!"😇
I think ambient temperature would be lower if it weren't in the middle. Since all three samples were together and the silver one in the middle didn't get much airflow around it. It would be better to separate them a few feet.
I'd like to see this repeated in winter, how much if any would your house get back. Some of us have far more heating days than cooling.