Why are 99% of US roofs still black? Residential, commercial, they're all some variation of black tar.
It seems almost cheating to simply change their reflectivity for a huge cooling power savings.
It seems almost cheating to simply change their reflectivity for a huge cooling power savings.
15 years ago I put a white, metal roof on my house, my summer cooling costs are half or less my neighbors' with the shingled roofs, and they've replaced their shingles in that time frame.
The crop duster aircraft also use my house as a navigation marker and we get to see them frequently.
I'm struggling with the same decision right now. I have a small (2k sqft is small in this area) 300k structure and I don't know whether it will be worth lot value in 10-15 years or still worth 300k+inflation+value additions. The surrounding neighborhood with 1-2million dollar structures says "lot value" even if it's pristinely maintained.
It is one of those upgrades you can add to a house that actually retains its value when you go to resell... Most metal roofs have lifespans that are minimum double that of shingles and, per your example, solar panels.
Of course, most people buying in the countryside aren't intending on moving out in fewer than 6 years; 7 minimum is generally considered the break even point around here.
It sounds like your area is one where the location and the market determine value far more than anything on the land, so treat it as "build to suit" commercial property and assume anything built on it is disposable.
Shingles are almost always more expensive because of laborious installation.
Its nowhere near as loud as an aluminum skinned mobile home.
Not just black. Dark, fractulate, nigh-furry extremely light-absorbing black.
It's like they designed it to soak up sun and get hot. So hot that it starts to melt. So hot that you need to use special nails so they don't pull through the half-melted black goo.
Anything would be an improvement.
I like white painted steel.
The other side is that having a roof which warms itself in winter is better for reducing snow accumulation. Though that’s also less of a consideration for a slippery metal roof.
Plus, in practice, you'll want a ton of insulation between the interior space and the roof anyway. So if you've done a good job there it's kind of a moot point wrt/interior comfort. But sending that power back into space rather than absorbing it can reduce thermal cycle stress on the roof and keep the outdoor space nearby cooler.
So much wrong here. Asphalt shingles neither "retain heat" nor "warm themselves." You really do not want either property in a roof covering in a climate where it snows because that will cause the formation of ice dams. If you have snow on your roof, it obviously covers the black shingles - now you have a white roof anyway. If it is winter and you do not have snow on your roof, it is still not worth it - solar irradiance at 50° latitude (approximately Timmins, Ontario) is going to be about a factor of 7 less in January than in June. You are much better off with a white roof in northern Canada to reduce peak heat stress in the summer, which will continue to get worse and worse due to greenhouse gasses.
We had a steep roof in the Okanagan which rose about 20ft to the peak. That extra room was problematic in winter for heating but a life saver in the hot, sunny summer. The loft was unbearable during the summer.
A neighbor with a low roof would run a sprinkler on his roof all summer long, that's how bad the heat would get.
My previous house already had a light colored metal roof, and my current one is shingles that are not due to be replaced for another ten years or so, but these are good things to think on.
Residential buildings usually have sloped roofs visible from the ground so the roof color is an architectural choice. Depending on the locale, current building codes can require enough roof insulation that very little heat flows through the roof in either direction. The insulation has an added benefit of preventing heat loss in the winter.
In NYC we use black tar to seal the roof, but then it is painted silver or white. You almost never see an actual black or dark colored roof.
Most white paints used nowadays contain titanium white.
Nevertheless, many white plastics contain other white pigments instead of titanium white. Titanium white itself is inert, but when it is exposed to the sun light it can catalyze the destruction of organic substances like plastics or paint binders that have not been selected to be resistant to this.
So when using titanium white outdoors, the white paint must be specified as UV resistant.
I have not heard about paper that uses titanium white.
That might be due to the higher cost of titanium white, which might be too much compared to the cost of paper.
The barium that might have leached will be precipitated by the carbon dioxide from the air into barium carbonate.
Any form of soluble barium left in the environment will end soon as either barium sulfate or barium carbonate, which are insoluble, thus non-poisonous.
Barium is one of the least dangerous metals with high atomic number. You have to do something really stupid and deliberate with it in order to be able to poison anyone.