As cities heat up, reflective roofs could lower energy bills and help the climate. But dark-roofing manufacturers are waging a quiet campaign to block new rules
Painting roofs white and creating lighter coloured pavements and roads are recognised as ways to reflect heat in urban areas and help combat global heating. However, a new study shows that this geoengineering technique unexpectedly causes temperatures to rise in the surrounding region.
We have hundreds of years of history where civilizations have concluded that white roofs are cooler. We have decades of modern academic research that backs that up.
One study indicating the opposite may be true in some cases is not sufficient evidence to start overturning legislation. It’s not enough to start submitting to the lobbying of these huge corporations trying to sell darker roofing materials. It IS enough to call for more research into the matter, and if enough research confirms this new finding THEN we start changing laws.
I cannot imagine any way that a dark roof would absorb less heat than a light roof. By definition a dark roof absorbs more light than a light roof, that’s why they appear dark/light.
I’d be interested in reading this one study though, if you have a link
The “one study” I was referring to was in response to the previous commentor,and this is the link they had.
I am just as skeptical as you are. The argument they seem to be making is that white roofs reflect heat back into the atmosphere instead of absorbing it, which leads to reduced cloud cover and rainfall. Their conclusion is that white roofs result in lower temperatures locally, but higher temperatures across larger regions.
They could potentially be on to something, but it’s also possible that either they are mistaken or biased by the same money these corporations are throwing at legislatures.
But we also have a lot of data about how reduced ice coverage in places like Greenland is resulting in a positive feedback loop that increases temperatures in part because more light gets absorbed by the ground and less gets reflected back, which leads to more ice melting. If this one study is correct, I would expect to see much more stable temperatures and ice sheets in the poles than we see today and have seen historically.
It’s just microclimates. I particularly hate the article’s framing of white materials as “geoengineering”, which implies that black asphalt roofs and roads are somehow not. We also know urban heat islands shift moisture downwind. So they’ve modeled some micro interaction that shows piecemeal application of low and high albedo surfaces can possibly result in some weird local effects on precipitation, all packaged up for misinterpretation by EPDM manufacturers.
Meanwhile everyone with a brain knows that black asphalt and roofs are hotter than white surfaces. The solution is of course stop black roofs and the bate minimum amount of roads/parking lots, not try to make everything heat absorptive in the name of equality.
Oh yeah, the black roof industry produced a study that says that black roofs are better. I’d be highly skeptical, especially considering that ‘a study’ has no legal definition.
I’m a few days away from having a new roof installed (hurricanes 🙄), I chose a cool roof-compliant architectural shingle. So, I’ve done a bit of studying of this as well.
Based on my research, black roofs are still affected by the laws of thermodynamics, no matter how many lobbyists I surround it with.
You’re on point with that Greenland reference. That’s a very well studied phenomenon. I mean, assuming you believe scientists and observational data (which isn’t a guarantee here on social media).
Yes, dark colors absorb more heat. Trapping it and making the city hotter. Light colors reflect heat back, meaning the heat doesn’t stick around to heat up the area.
From the same publication:
Source: https://www.theguardian.com/news/2024/dec/05/weatherwatch-why-cooling-white-roofs-cause-neighbours-to-swelter
We have hundreds of years of history where civilizations have concluded that white roofs are cooler. We have decades of modern academic research that backs that up.
One study indicating the opposite may be true in some cases is not sufficient evidence to start overturning legislation. It’s not enough to start submitting to the lobbying of these huge corporations trying to sell darker roofing materials. It IS enough to call for more research into the matter, and if enough research confirms this new finding THEN we start changing laws.
I cannot imagine any way that a dark roof would absorb less heat than a light roof. By definition a dark roof absorbs more light than a light roof, that’s why they appear dark/light.
I’d be interested in reading this one study though, if you have a link
https://www.theguardian.com/environment/2025/jun/01/dark-roof-lobby
The “one study” I was referring to was in response to the previous commentor,and this is the link they had.
I am just as skeptical as you are. The argument they seem to be making is that white roofs reflect heat back into the atmosphere instead of absorbing it, which leads to reduced cloud cover and rainfall. Their conclusion is that white roofs result in lower temperatures locally, but higher temperatures across larger regions.
They could potentially be on to something, but it’s also possible that either they are mistaken or biased by the same money these corporations are throwing at legislatures.
But we also have a lot of data about how reduced ice coverage in places like Greenland is resulting in a positive feedback loop that increases temperatures in part because more light gets absorbed by the ground and less gets reflected back, which leads to more ice melting. If this one study is correct, I would expect to see much more stable temperatures and ice sheets in the poles than we see today and have seen historically.
It’s just microclimates. I particularly hate the article’s framing of white materials as “geoengineering”, which implies that black asphalt roofs and roads are somehow not. We also know urban heat islands shift moisture downwind. So they’ve modeled some micro interaction that shows piecemeal application of low and high albedo surfaces can possibly result in some weird local effects on precipitation, all packaged up for misinterpretation by EPDM manufacturers.
Meanwhile everyone with a brain knows that black asphalt and roofs are hotter than white surfaces. The solution is of course stop black roofs and the bate minimum amount of roads/parking lots, not try to make everything heat absorptive in the name of equality.
Oh yeah, the black roof industry produced a study that says that black roofs are better. I’d be highly skeptical, especially considering that ‘a study’ has no legal definition.
I’m a few days away from having a new roof installed (hurricanes 🙄), I chose a cool roof-compliant architectural shingle. So, I’ve done a bit of studying of this as well.
Based on my research, black roofs are still affected by the laws of thermodynamics, no matter how many lobbyists I surround it with.
You’re on point with that Greenland reference. That’s a very well studied phenomenon. I mean, assuming you believe scientists and observational data (which isn’t a guarantee here on social media).
Yes, dark colors absorb more heat. Trapping it and making the city hotter. Light colors reflect heat back, meaning the heat doesn’t stick around to heat up the area.
So if everyone has a white roof, the perimeter heating effect would be negated?