4 ms·

Someone correct me if I'm wrong, but isn't there more energy used to heat buildings than cool them? Of course it depends on many factors, including location; so

by 8plot 17y ago

Someone correct me if I'm wrong, but isn't there more energy used to heat buildings than cool them? Of course it depends on many factors, including location; so a blanket statement of "white roofs everywhere" seems wrong.

ars 17y ago
It strongly depends on where you live. But very little of the heat from the roof gets in the building in the winter. Mainly because it's insulated. But also because hot air rises, so little of it travels down to the building space. But A/C is with vents, AKA air currents, so may be more effective at capturing heat from ceilings. But all that ignores the fact that white paint does not survive. In Tuscon the roofs would have white rocks on the roof. I strongly doubt you could make a white roof paint that would survive for more than a few years. How about shiny aluminium roofs? As a side note, I always wondered why metal roofs are not more popular. Aluminium would last pretty much forever, and it doesn't have to be one piece - you can make it into shingles for easy installation.
- jnorthrop 17y ago
  "As a side note, I always wondered why metal roofs are not more popular. Aluminium would last pretty much forever, and it doesn't have to be one piece - you can make it into shingles for easy installation." When I re-shingled my roof a couple of years back I looked into metal roofing. The cost was almost double asphalt roofing shingles. Although a metal roof would last longer (25 years vs. 50 years), but if you wanted durability and cost wasn't an object slate roofs are expected to last 75 years or more (at least here in Maine). Of course a white roof here is useless -- I don't even own air conditioners.
- dan_the_welder 17y ago
  As far as shiny aluminum goes, it's my experience that it does not remain shiny for long. A coating that kept it shiny would increase cost as well as the process of making it mirror finished in the first place. Once the coating failed there would be no practical way to re-polish and recoat to anywhere near factory quality and there goes your efficiency. In Florida a dull aluminum surface will be much hotter than a white painted one. Metal roofs are not as popular as they should be because the capitol cost is more and they are often considered low class. These days there are several fancy metal roofing systems that are more popular than 5 V crimp and the classic corrugated. I personally like the classic standing seam style which I saw a lot of in Maine and New Hampshire and are installed by skilled craftspeople. Asphalt shingles are made from the cheap and plentiful byproducts of the oil refining process and crushed rock. They are made from dirt and installed by low skilled labor.

by 8plot 17y ago

ars 17y ago

It strongly depends on where you live. But very little of the heat from the roof gets in the building in the winter. Mainly because it's insulated. But also because hot air rises, so little of it travels down to the building space. But A/C is with vents, AKA air currents, so may be more effective at capturing heat from ceilings. But all that ignores the fact that white paint does not survive. In Tuscon the roofs would have white rocks on the roof. I strongly doubt you could make a white roof paint that would survive for more than a few years. How about shiny aluminium roofs? As a side note, I always wondered why metal roofs are not more popular. Aluminium would last pretty much forever, and it doesn't have to be one piece - you can make it into shingles for easy installation.

jnorthrop 17y ago
"As a side note, I always wondered why metal roofs are not more popular. Aluminium would last pretty much forever, and it doesn't have to be one piece - you can make it into shingles for easy installation." When I re-shingled my roof a couple of years back I looked into metal roofing. The cost was almost double asphalt roofing shingles. Although a metal roof would last longer (25 years vs. 50 years), but if you wanted durability and cost wasn't an object slate roofs are expected to last 75 years or more (at least here in Maine). Of course a white roof here is useless -- I don't even own air conditioners.
dan_the_welder 17y ago
As far as shiny aluminum goes, it's my experience that it does not remain shiny for long. A coating that kept it shiny would increase cost as well as the process of making it mirror finished in the first place. Once the coating failed there would be no practical way to re-polish and recoat to anywhere near factory quality and there goes your efficiency. In Florida a dull aluminum surface will be much hotter than a white painted one. Metal roofs are not as popular as they should be because the capitol cost is more and they are often considered low class. These days there are several fancy metal roofing systems that are more popular than 5 V crimp and the classic corrugated. I personally like the classic standing seam style which I saw a lot of in Maine and New Hampshire and are installed by skilled craftspeople. Asphalt shingles are made from the cheap and plentiful byproducts of the oil refining process and crushed rock. They are made from dirt and installed by low skilled labor.