A white or light colored metal roof will be significantly better than shingles, and will off-load heat quicker at night, too. But, a metal roof costs more than asphalt shingles.

See industry link below for more research.

Here is a link that might be useful: Cool Metal Roofing

Does anyone make a cool roof product that LOOKS like traditional grey asphalt shingles?

My taste is a bit too traditional.

I too am looking for a cool roof in a traditional looking asphalt shingle and so far the only manufacturer I've come up with is GAF - Elk's Prestique Cool Colors shingles.

And - wouldn't you know it - when I asked about price I was told the cool colors are nearly twice the cost of non-cool colors.

Here is a link that might be useful: cool roof

bevangel, do you remember how the cost of the Elk "cool roof" shingles compared to metal roofing? It sounds like it would be almost as expensive as going with standing seam.


------------ Trilby

Trilby23, I was quoted a price of $142/square for Elk Prestique Cool Colors while the Elk Prestique in regular colors was $82/square. Sorry but I don't recall the price of standing seam except that it was way beyond my pocketbook. (Seems like it was in the neighborhood of $275 to $300 per square.)

MightyAnvil, what I was talking about are architectural shingles that, instead of being made with dark colored granules, are made with light colored granules that reflect significantly more of the sun's rays so that less heat enters the attic space to begin with. This is regardless of what type of insulation one has within the attic and whether it is a vented or unvented attic. Higher reflectivity results in a cooler attic which can be helpful regardless of the amount of insulation one has. Apparently roofing companies have decided that people don't like light colored roofs. I for one bought the lightest color shingle I could find when we had to put a new roof on our current home ten years ago and I and would gladly have gone with an even lighter color if any had been available.

BTW, a couple of companies do make white roofing shingles BUT for some reason, they only seem to make them in their lowest quality, thinnest, 3-tab shingles. Their "better" and "best" shingles are only available in darker colors.

None of the distributors in my area carry any of the white ones because such thin shingles won't really stand up to the winds we commonly have. Around here, the biggest fanciest homes all have metal roofs either left silver or painted white so I'm sure the middle market would happily use white shingles if a heavy duty one were available. Unfortunately, since we can't afford metal, our only option is the Elk Prestique Cool Colors. And, at this point, that too seems out of our budget especially as, as MA points out, it would be better to use the extra $60/square for more insulation anyway.

Independent field tests have shown that venting roofs does very little to reduce the temperature of asphalt shingles and that light colored shingles are much more effective in that regard. But some (not all) shingle manufacturers still void a warranty if the roof is not vented and give no consideration to roofs with lighter colors.

Most information available about asphalt shingles (like the "cool roof" idea) is made up by manufacturers in an effort to sell more shingles at higher prices and pay as few warranty claims as possible. This nonsense about venting has been very profitable for them and most companies still refuse to give it up.

One thing to keep in mind about all light-colored roofs: local pollution. All roofs are going to have pollution settle on them; you don't notice it on dark colors, although if you look at the window washing water, you'll see what lands on the house's exterior surfaces. If you are depending on white or light gray for reflectivity, then keep in mind that the loss of reflectivity can be as much as 25% to 40% after 3 years (dependent upon the quality of your local air). I am about 20 miles from a large city [very low industrial emissions], and within 3 years my "white" roof was light gray. With that knowledge, I wouldn't worry especially about getting a "white" roof, and would be content with the lightest available color within the variety offered.

I've not read any studies on the subject, but I do wonder if the 'slickness' of metal or tile roofs (as opposed to gravelled shingles) might help them become cleaner during a normal rain. It seems to me that the more dirty pollution that is washed off with each rain, the longer a higher reflectivity could be maintained.

trilby- the cost of a standing seam metal roof will far surpass even the most expensive asphalt roofing material. Not only will the material cost be more expensive, but the cost of the install will be at least double. The reasons for choosing a metal roof over an asphalt roof are plentiful (IMO) but comparable cost is definitely not one of them.

A lighter granule or lighter colored shingle might provide miniscule results compared to a darker shingle, but whatever the color type, it's the asphalt base that, when heated up, retains the heat. The "cool" shingle route you are seeking will only provide minimal results and not an effective block for heat gain. For an effective treatment of your project, open up your wallet and look in the direction that mighty anvil steered you with foam panels, radiant barrier, venting, etc.

I'll put it another way. A lighter colored or more reflective roofing material might reduce the temperature of the interior ceiling by 5 degrees. But you need to reduce the temperature many times that amount. That can only be done with insulation.

If you can't add insulation on the inside you must put it on the outside. If you are worried about asphalt single warranties requiring a vented roof (some only reduce the warranty period which is fine since the coverage is pro-rated anyway) you can try the product linked below.

Here is a link that might be useful: ventilated sheathing on insulation board

bevangel and dixiedoodle, thanks for the input! We want standing seam very much, but I can't imagine that we'll be able to afford it. I hope that we'll be able to at least consider the Cool Roof shingle option.


------------ Trilby

As stated above, the cool shingle route isn't going to accomplish what you are after efficiently. By paying more now for proper insulation/barrier/venting, you will save money in the long run and more important, accomplish an easier to cool interior.

Concerning roofing, you would be better off running a torch down built up roof and coat with a reflective elasomeric coating in white or silver. It woud give you more reflectivity than any shingle type, but still wont achieve what you are after,imho. The coatings aren't recommended over shingles.

Even if "cool" roof shingles could reduce the temperature of a roof by 10% (and that has yet to be demonstrated by any manufacturer) it would not reduce the temperature of the room below by as much as a small amount of insulation. Don't waste your money trying to cool your roof, insulate it.

I have been researching products to help my roof/attic in Phoenix. I have started to deploy Radiant barriers, but have thought that the best spot is on the exterior of the home.

The price for metal shingles (Decra) seems to be in the $400 to $600 a square. A bit expensive.

The GAF/ELK shingle could be a miracle product. If they were really created in conjunction with 3M, then there is a liklihood these shingles have the ceramic (borosilicate spheres) in them. This is what is used in Ceramic based radiant barrier paints.

The insulate to the max thought simply is not correct in the high heats of the desert. See the story at the link. Emissivity and Radiant barriers are explained. As is adequate Attic Venting. Something else that is usually not done correctly.

Regarding the reduction of attic heat, one of the local GAF reps had sited GAF data that showed an attic would only be 22 degrees above ambient if ...you used their ridge vents and proper soffit vents, to the tuneof 1/150 of the attic square footage. Split as half input and half output.

Consider this: you could have R30 or more in an attic with improper venting or even improper radiant barriers installation. The attic super heats to 50 to 100 degrees above ambient. Guess what. You now have attic insulation that is at 175 degrees. WHen the sun goes down, that is the new heat source....dumping its heat into your home. CHeck it out with a heat gun. Or simply monitor your ac late in the afternoon and after sundown. Instead of slowing down, it is running more!

The GAF cool roof are twice as much as regular because of the mark up for this reflective/emissive properties. However, realize these are 40 year shingles. Not the whimpy versions at the local home stores. So between solar performance and longevity, it is a lot more than $40 per bundle fiberglass. Yet still a lot cheaper than metal.

Yes, metal roofs, with a batten, will indeed chimney very well. Go to the OakRidge National Laboratory site to see about cool roof studies and results. One case compared the results of 12 study homes. Very interesting.

When you look at the white papers on the Horizon ENergy site, you can see how well a non traditional home can actually perform using radiant barrier technology and NOT insulating to the limits an attic.

I may even be motivated to instrument my attic with thermal sensors Before and After the shingle changeout. In the meantime my roof leaks...and it must be replaced.

Here is a link that might be useful: Horizon Energy

Well, what would you all recomend for a story and a half home where most of the living space is up-stairs within the 12/12 roof?

Hot and humid south east