As I've been learning more about trying to one day build my dream green home I've come across metal roofs.  I like the way they look and they can offer some nice advantages for clean energy and energy conservation, including:

• No need for replacement like shingle roofs = more long term sustainability
• Recyclable at the end of life
• Reflects more heat than a shingle roof = great for hot climates
• Great for rainwater collection systems
• Ease of install for solar PV systems
  

Another advantage is that they hold up very well in storms as you don't have to worry about losing shingles. Houzz.com had a great article on the advantages of metal roofing (it was the inspiration for this post).

Home energy expert and another Atlanta based blogger, Allison Bailes of Energy Vanguard had this to say about metal roofs:

I like metal roofs and installed one on the house I built. The can help with cooling in hot climates and probably have a lower lifetime embodied energy cost than shingles because they don't need to be replaced as frequently.

The biggest disadvantage is a higher initial cost compared to an asphalt shingle roof.   Hometips.com also has a great list of advantages and disadvantages of a metal roof.  One of those disadvantages I really didn't think of is the roof getting dented during a hail storm, although I guess this happens to shingle roofs as well.

There is a federal tax credit for metal roof (with appropriate pigmented coatings) and even asphalt roof (with cooling granules) is available that covers 10% of the cost of the roof (up to $500).

Do any of you have experience with metal roofs?  Other than liking the way they look (and writing a blog post), I don't know much about them.