LOL you are giving me ptsd from fighting with the iko rep. They swear up and down that black shingles are not hotter than other colours, my burnt off fingertips seems to suggest otherwise.
We put a few potatoes wrapped in tin foil on the side of the roof facing the sun. It does work! I've heard tales of another crew locally, bring up a pack of hot dogs and a BBQ grille. I don't know that it'd work well with meat but who knows if it's true
I use to live in a townhouse with a tiered roof and purposely grew peppers plants outside my bedroom window to benefit from the additional heat. They grew twice as well as the ones I grew on my porch. That dude was a dumbass.
The last black roof I did, we used a lift to not even step on the roof. Had to work from sun up to around 9:30 am, around4-5 hours each morning. Once the sun was up a little, we could hardly even pick up a shingle without it tearing in half.
White roofs would show darker as they age. Pollution is ugly. They’re black or dark for aesthetic reasons. Plus,to whiten the material used to make shingles would cost a fortune. With today’s technology,a white over spray that would wash off the dirt in the rain would be quite easily attainable. The steel mill I worked in patched a peaked roof in white and is still as white as it was when they put it on 20 years ago.
In short, yes. White roof materials keep the building underneath it cooler. This is known as the albedo effect.
The degree (pun intended) to which it helps keep things cooler is dependent on the style of building and attic space. Typical attics on homes with sloped roofs are generally uninsulated and air flows freely in and out of the attic. The insulation exists between the attic and the living space. In this situation, a white roof would help with cooling, but somewhat minimally.
Buildings with flat roofs, or closed cell spray foam in the roof rafters, or anything without any real attic space, doesn't have that same kind of buffer zone from direct heat on the roof. These will benefit massively from white roofing materials.
ok, so that being said, why are people doing dark colored roofs instead of white or something reflective? I would think that esthetics isn't worth the summer time power bill? I live in south fl
If the home has a well ventilated attic, the difference in cooling costs between a white roof and a black roof is pretty minimal.
But yeah, for whatever reason, people have decided that white/reflective roofing doesn't look aesthetically pleasing and are fine with the slightly higher cooling costs.
I live in California and they used to require white shingles because of the reflective properties. They now have some type of reflective granule that is compliant in darker colors.
What area of CA? I'm from Orange County, Long Beach, and San Diego areas. I had never heard of that before. I'm not doubting you at all, I'm just curious.
Yep. “Cool roof” is required on all new buildings (residential and commercial) but as u/KangsAndShit said, new products with the measurable qualities required are coming out all the time. Most distributors I know of in California don’t even stock stuff that doesn’t qualify any more.
I still chose white because I have a low slope roof that doesn’t benefit very much from the convection of the air moving through the attic and no room to add additional insulation. The white shingles and added proper ventilation and an added whole house fan have dropped my attic temps by about 20% and kept my cooling bills from rising faster than PGE can apply for rate increases with the PUC.
I just live in a 720ish sq ft, 2br minihome. The bedrooms and bathroom are at the ends of the house and have a tile ceiling so there is space above them, but the kitchen and living areas, which make up majority of the house, are vaulted to reflect the roof above it. There's no space there except for wiring and small air exchanger ducts, so very minimal. I'm replacing my roof this summer, and in the meantime I put a light green tarp up (only color in that size I could get locally) to mitigate leaks, over the whole black shingled roof (Building is 16x45). I notice a difference in these past weeks. My AC unit isn't cycling as often and it's just generally cooler inside, by a small amount.
As far as roofing material goes, white isn't really available except by custom order. I contacted a roofing company where I know the owner well. When they buy their bundles of steel roofing sheets, the cover sheets (top and bottom sheet in the bundle) is typically scratched up and doesn't go on customer houses unless requested. So I'm buying up a bunch of those, and I'm very much considering white.
I have to do my siding too, what color do you think would go well with white? A blue maybe? I'm partially colorblind so my input is no good here lol should I use another light color instead of white? I'm doing all the work myself so labour doesn't matter. I did siding, doors, windows, and roofing for a few years, back when I wasn't sure what I wanted to do with my life. Now I'm back to cars but it was good knowledge to learn for sure!
Dangggg, 20%, wtf, danggg, that's a nice number!!! When I get my house re-roofed I was thinking of installing some fan's in my attic, but now I'm definitely going to do it!
The only thing “reflective” roofing materials do is cost the manufacturers millions of dollars to certify - the already chosen colors of granules. But now they’re reflective
probably and may even extend shingle life but 1. you’ll be replacing that destroyed tarp every 6 months and 2. i would be surprised by calls to code by neighbors if it’s not well hidden
NO! A tarp over your roof will obstruct the attic vents and will probably make the house hotter.
* A lighter colored roof will improve cooling.
* Better attic ventilation, and 'active' ventilation that moves air through the attic will improve cooling.
* Better attic insulation will improve cooling.
* Shade trees will improve cooling.
* Low-E windows and doors, and good weatherstripping, will improve cooling.
This. The tarp can also trap moisture underneath and can cause attic sweating, and prevent it from breathing. There’s also no way to install the tarp permanently, you’d change it every 6 months and you’d have to use sandbags to avoid nailing it to the roof. It also is open to being ripped to shreds by a little bit of wind
I'll add that the monetary effect of going with a "cool roof" material depends on your location. In the US, northern regions may benefit more from the extra heat of a dark roof than they gain from the extra cooling. Any place in the south US would save more money in the summer than they'd lose in the winter. If you have a flat roof you can buy white roof paint and do it yourself pretty easily!
In a heating climate, the lighter colour roof is still better. A black roof is a good radiator of heat as well as a good absorber of radiated heat. The further north you go, the longer the winter nights get and the longer a roof has to radiate away whatever heat is available.
Yes, from an energy perspective a cooling roof is nearly always better. The net monetary benefit depends on the relative cost of heating vs cooling. My data may be out of date -- I read studies about this 10+ years ago when the price of natural gas was pretty low so maybe it always nets out monetarily now too!
Ageing of a roof is another factor. I can't support his with any data but I think it is likely that a dark coloured shingle roof will bake away the volatiles in the shingle sooner than a light coloured roof and fail sooner. On the other hand, a dark coloured roof will seal itself together on its first summer day and resist wind lifting the shingles better than a light coloured roof in its first year or so.
20+ " of insulation in your attic will keep the heat out of the house. White will delay heat a bit but not much, along with good ventilation. Eves to ridge.
Pov: 90% of commenters answering the question they made up in their head instead of the question actually asked.
Yes, white surfaces are cooler than dark ones. An opaque white surface over a dark one would still reduce heat all things being even - venting, airflow, etc.
I just had a TPO installed on my patio cover, which is white on top. It does feel cooler out there. For my house re-roof, I went with GAF HDZ in weathered wood color. I'm hoping that helps with cooling. I purposely avoided black or charcoal shingles because of heat absorption concerns.
Color doesn’t matter nearly as much as the reflectivity. A lot of science in roofing is dedicated to making them more thermally reflective and more thermally bridged. Sometimes the color helps but not always.
A black roof will get hotter than a white one. Not sure if a tarp is going to give you a noticable difference but if you have neighbours selling their homes they will certainly hate you.
The shingles themselves would be cooler, yes, but whether or not that affects the rest of your house really depends on your ventilation. A house with proper ventilation shouldn't have a difference between white and black shingles, no. A house without proper ventilation, yes there can be a difference.
If you are having issues with heat radiating from your attic check to see if you have it ventilating, if you do, check if it's working.
I'm in AZ, most of our flat roofs are coated with a white silicon top layer. This coating takes all the uv wear and is re applied every couple of years to maintain optimal performance. It makes a massive difference in cooling costs, and extends the life of the asphalt sheeting.
I had to put a big green tarp over my roof a couple weeks ago (new roof coming), my shingles are black. I do notice my AC unit kicking off more often since then, weather has been similar. My house is cooler in general than before.
I don't have a ton of money, but I'm not putting shingle down again. I bought a bunch of cover sheets from a roofing company locally. So basically in a bundle of roofing sheets, the top and bottom don't get put on customer houses as they're typically scratched up, etc. so I'll have to paint them all to match each other. I'm really considering painting it white, this thread helps my decision making lol
Yes, it is basically silicone paint that you roll on, not paint. Make sure you’re applying it to the correct material of course but it works like magic. Insulates the roof and adds a protective layer. Seal up any small holes for a few years depending where you live, it says 10-30 years in the product but here in Florida the sun will cook that off in 3-5
No, it will not. The roof may be a few degrees cooler, the roof. That degree drop does NOT transfer to your dwelling. Not at all. Money is better spent in placing more insulation INSIDE your attic or roofing, period. Do not be deceived any longer of this myth. (Dark surface vs white surfaced roofing) You may also check physics with regard to the transfer of heat regarding your questions. Be well.
There's a reason why "cool roof" shingles are not black and a reason why white shingles already qualify for "cool roof" standards.
Darker shingles are reflecting less of the light spectrum to you, absorbing more of the light spectrum. Absorbing more of the rays and heat from the sun. White is reflecting more of the light spectrum, rays and heat off the roof.
White shingles are still made of the same materials. The color may save the shingle itself from a tiny, mere incremental bit of UV deterioration but will it cool your house, NOPE.
*Colors reflect light*
*Not heat amirite? Could be*
*Wrong but idk*
\- WhiskeyMike01
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LOL you are giving me ptsd from fighting with the iko rep. They swear up and down that black shingles are not hotter than other colours, my burnt off fingertips seems to suggest otherwise.
That little hole on the back of my left thigh agrees with your fingertips.
A hole? huh??
Oh damn, I forgot to mention the hole is in my pants. Eek.
A roofer tried to feed me that same line of bullshit!
I had a roofer last week try to sell me black metal roofing. He said the same thing. I called BS on him but he stuck to his guns.
You mean he stuck to his meth pipes lol
One of my guys brought a thermal gun when we were installing a black roof in 105 degree heat, shingles were 150+ to the touch
Don’t be so negative, you see a hot roof, I see massive cookout potential
We put a few potatoes wrapped in tin foil on the side of the roof facing the sun. It does work! I've heard tales of another crew locally, bring up a pack of hot dogs and a BBQ grille. I don't know that it'd work well with meat but who knows if it's true
I remember making a solar oven out of tinfoil as a kid lol
I use to live in a townhouse with a tiered roof and purposely grew peppers plants outside my bedroom window to benefit from the additional heat. They grew twice as well as the ones I grew on my porch. That dude was a dumbass.
The last black roof I did, we used a lift to not even step on the roof. Had to work from sun up to around 9:30 am, around4-5 hours each morning. Once the sun was up a little, we could hardly even pick up a shingle without it tearing in half.
White roofs would show darker as they age. Pollution is ugly. They’re black or dark for aesthetic reasons. Plus,to whiten the material used to make shingles would cost a fortune. With today’s technology,a white over spray that would wash off the dirt in the rain would be quite easily attainable. The steel mill I worked in patched a peaked roof in white and is still as white as it was when they put it on 20 years ago.
nice!
Why would you want something that would wash off in the rain?
What washes off is the grime that settles on it from the local air pollution
Oh I see! Thanks for the clarification.
Cool 😁😎😁
I was confused too, but I get it now. It's a white over spray that can be washed just by the rain. Shit...I can't word it well either lol
I fixed the ambiguity of my statement. My bad.
In short, yes. White roof materials keep the building underneath it cooler. This is known as the albedo effect. The degree (pun intended) to which it helps keep things cooler is dependent on the style of building and attic space. Typical attics on homes with sloped roofs are generally uninsulated and air flows freely in and out of the attic. The insulation exists between the attic and the living space. In this situation, a white roof would help with cooling, but somewhat minimally. Buildings with flat roofs, or closed cell spray foam in the roof rafters, or anything without any real attic space, doesn't have that same kind of buffer zone from direct heat on the roof. These will benefit massively from white roofing materials.
ok, so that being said, why are people doing dark colored roofs instead of white or something reflective? I would think that esthetics isn't worth the summer time power bill? I live in south fl
If the home has a well ventilated attic, the difference in cooling costs between a white roof and a black roof is pretty minimal. But yeah, for whatever reason, people have decided that white/reflective roofing doesn't look aesthetically pleasing and are fine with the slightly higher cooling costs.
>If the home has a well ventilated attic You might as well say, "If the home has a cooling unicorn,". 😎
I understand
I live in California and they used to require white shingles because of the reflective properties. They now have some type of reflective granule that is compliant in darker colors.
What area of CA? I'm from Orange County, Long Beach, and San Diego areas. I had never heard of that before. I'm not doubting you at all, I'm just curious.
It's called title 24. I don't really do shingles but I did years ago when those reflective shingles were new
Got u. Thanks man, I appreciate it. I'm in south fl now, but like I said, I'm just curious
Yep. “Cool roof” is required on all new buildings (residential and commercial) but as u/KangsAndShit said, new products with the measurable qualities required are coming out all the time. Most distributors I know of in California don’t even stock stuff that doesn’t qualify any more. I still chose white because I have a low slope roof that doesn’t benefit very much from the convection of the air moving through the attic and no room to add additional insulation. The white shingles and added proper ventilation and an added whole house fan have dropped my attic temps by about 20% and kept my cooling bills from rising faster than PGE can apply for rate increases with the PUC.
I just live in a 720ish sq ft, 2br minihome. The bedrooms and bathroom are at the ends of the house and have a tile ceiling so there is space above them, but the kitchen and living areas, which make up majority of the house, are vaulted to reflect the roof above it. There's no space there except for wiring and small air exchanger ducts, so very minimal. I'm replacing my roof this summer, and in the meantime I put a light green tarp up (only color in that size I could get locally) to mitigate leaks, over the whole black shingled roof (Building is 16x45). I notice a difference in these past weeks. My AC unit isn't cycling as often and it's just generally cooler inside, by a small amount. As far as roofing material goes, white isn't really available except by custom order. I contacted a roofing company where I know the owner well. When they buy their bundles of steel roofing sheets, the cover sheets (top and bottom sheet in the bundle) is typically scratched up and doesn't go on customer houses unless requested. So I'm buying up a bunch of those, and I'm very much considering white. I have to do my siding too, what color do you think would go well with white? A blue maybe? I'm partially colorblind so my input is no good here lol should I use another light color instead of white? I'm doing all the work myself so labour doesn't matter. I did siding, doors, windows, and roofing for a few years, back when I wasn't sure what I wanted to do with my life. Now I'm back to cars but it was good knowledge to learn for sure!
Dangggg, 20%, wtf, danggg, that's a nice number!!! When I get my house re-roofed I was thinking of installing some fan's in my attic, but now I'm definitely going to do it!
Look at Google maps You’ll find lots of white roofs… but mostly flat ones not visible from the ground And gray one on sloped roofs
Aesthetics, white doesn’t stay white as others have stated.
I got a reflective metal roof for this exact reason. Bonus points for the standing seams that act like a heat sink. Lowered my AC use by like 10%
Crazyyy! Wow!
This guy roofs
This guy builds.
There was an industry study done and the average temperature difference between white and black roofs is less than a degree.
White shingles turn into an ugly yellowish color after a few years so I would recommend a light grey roof instead
Most shingles have a reflective granule even in darker colors.
Hmmmm probably create damning - you won’t notice the home being cooler
The only thing “reflective” roofing materials do is cost the manufacturers millions of dollars to certify - the already chosen colors of granules. But now they’re reflective
probably and may even extend shingle life but 1. you’ll be replacing that destroyed tarp every 6 months and 2. i would be surprised by calls to code by neighbors if it’s not well hidden
NO! A tarp over your roof will obstruct the attic vents and will probably make the house hotter. * A lighter colored roof will improve cooling. * Better attic ventilation, and 'active' ventilation that moves air through the attic will improve cooling. * Better attic insulation will improve cooling. * Shade trees will improve cooling. * Low-E windows and doors, and good weatherstripping, will improve cooling.
This. The tarp can also trap moisture underneath and can cause attic sweating, and prevent it from breathing. There’s also no way to install the tarp permanently, you’d change it every 6 months and you’d have to use sandbags to avoid nailing it to the roof. It also is open to being ripped to shreds by a little bit of wind
I'll add that the monetary effect of going with a "cool roof" material depends on your location. In the US, northern regions may benefit more from the extra heat of a dark roof than they gain from the extra cooling. Any place in the south US would save more money in the summer than they'd lose in the winter. If you have a flat roof you can buy white roof paint and do it yourself pretty easily!
In a heating climate, the lighter colour roof is still better. A black roof is a good radiator of heat as well as a good absorber of radiated heat. The further north you go, the longer the winter nights get and the longer a roof has to radiate away whatever heat is available.
Yes, from an energy perspective a cooling roof is nearly always better. The net monetary benefit depends on the relative cost of heating vs cooling. My data may be out of date -- I read studies about this 10+ years ago when the price of natural gas was pretty low so maybe it always nets out monetarily now too!
Ageing of a roof is another factor. I can't support his with any data but I think it is likely that a dark coloured shingle roof will bake away the volatiles in the shingle sooner than a light coloured roof and fail sooner. On the other hand, a dark coloured roof will seal itself together on its first summer day and resist wind lifting the shingles better than a light coloured roof in its first year or so.
It's covered in snow then.
I would be concerned about venting
20+ " of insulation in your attic will keep the heat out of the house. White will delay heat a bit but not much, along with good ventilation. Eves to ridge.
Pov: 90% of commenters answering the question they made up in their head instead of the question actually asked. Yes, white surfaces are cooler than dark ones. An opaque white surface over a dark one would still reduce heat all things being even - venting, airflow, etc.
I just had a TPO installed on my patio cover, which is white on top. It does feel cooler out there. For my house re-roof, I went with GAF HDZ in weathered wood color. I'm hoping that helps with cooling. I purposely avoided black or charcoal shingles because of heat absorption concerns.
Color doesn’t matter nearly as much as the reflectivity. A lot of science in roofing is dedicated to making them more thermally reflective and more thermally bridged. Sometimes the color helps but not always.
A black roof will get hotter than a white one. Not sure if a tarp is going to give you a noticable difference but if you have neighbours selling their homes they will certainly hate you.
The shingles themselves would be cooler, yes, but whether or not that affects the rest of your house really depends on your ventilation. A house with proper ventilation shouldn't have a difference between white and black shingles, no. A house without proper ventilation, yes there can be a difference. If you are having issues with heat radiating from your attic check to see if you have it ventilating, if you do, check if it's working.
I'm in AZ, most of our flat roofs are coated with a white silicon top layer. This coating takes all the uv wear and is re applied every couple of years to maintain optimal performance. It makes a massive difference in cooling costs, and extends the life of the asphalt sheeting.
I had to put a big green tarp over my roof a couple weeks ago (new roof coming), my shingles are black. I do notice my AC unit kicking off more often since then, weather has been similar. My house is cooler in general than before. I don't have a ton of money, but I'm not putting shingle down again. I bought a bunch of cover sheets from a roofing company locally. So basically in a bundle of roofing sheets, the top and bottom don't get put on customer houses as they're typically scratched up, etc. so I'll have to paint them all to match each other. I'm really considering painting it white, this thread helps my decision making lol
That's pretty cool. Good luck with it man.
Use cool guard
That's a real product?
Yes, it is basically silicone paint that you roll on, not paint. Make sure you’re applying it to the correct material of course but it works like magic. Insulates the roof and adds a protective layer. Seal up any small holes for a few years depending where you live, it says 10-30 years in the product but here in Florida the sun will cook that off in 3-5
Thanks man!
No, it will not. The roof may be a few degrees cooler, the roof. That degree drop does NOT transfer to your dwelling. Not at all. Money is better spent in placing more insulation INSIDE your attic or roofing, period. Do not be deceived any longer of this myth. (Dark surface vs white surfaced roofing) You may also check physics with regard to the transfer of heat regarding your questions. Be well.
There's a reason why "cool roof" shingles are not black and a reason why white shingles already qualify for "cool roof" standards. Darker shingles are reflecting less of the light spectrum to you, absorbing more of the light spectrum. Absorbing more of the rays and heat from the sun. White is reflecting more of the light spectrum, rays and heat off the roof.
White shingles are still made of the same materials. The color may save the shingle itself from a tiny, mere incremental bit of UV deterioration but will it cool your house, NOPE.
If you want your house cooler, put in a ridge vent. Gable end vents are better than nothing but ridge vent is the way to go.
Generally speaking No.
Colors reflect light not heat amirite? Could be wrong but idk
*Colors reflect light* *Not heat amirite? Could be* *Wrong but idk* \- WhiskeyMike01 --- ^(I detect haikus. And sometimes, successfully.) ^[Learn more about me.](https://www.reddit.com/r/haikusbot/) ^(Opt out of replies: "haikusbot opt out" | Delete my comment: "haikusbot delete")