I'm renovating and I'm going to be doing a lot of work in my unfinished attic (rafters) in the coming months. I'd like to fully light the place up with permanent fixtures.

Since the area is smaller and more exposed to the elements than the finished areas of a house, are there any special requirements for lighting an attic? For example, could I simply hang uncovered, inexpensive, 4' fluorescent light? Or would I be required to use lighting designed for the outdoors? Are there any special requirements for how the fixtures should be positioned?

In regards to GFCI protection, I understand that I need to protect any outlets I may install in this area. What about the lighting however?

And finally, am I allowed to tap an existing lighting circuit for the attic, or do I need to run a new branch?

Thank-you!
Justin

Justin where do you live? Many fluorescent shop lights do not work well in cold, unheated areas. Will you be heating the attic or not. You don't mention plumbing so I don't think you will need GFCI outlets or were you planning something you did not mention. When remodeling a room it is good to have outlets and lighting on separarte circuits so you won't be in the dark if an outlet pops. I'd recommend pulling 2 new circuits if you can get from your panel to the attic. If not come back with the rest of your plans.
GFCIs Fact Sheet (http://www.cpsc.gov/cpscpub/pubs/99.html)

I live in Southern California, so it will rarely be below 50F. As for plumbing, there will be water and gas pipes running through the rafters as well.

What will be the final purpose of this attic?

When you say "there will be water and gas pipes running through the rafters ", I will assume you mean through the bays or voids between the rafters, and not actually drill holes through the wood framing that is the rafters.

What will be the final purpose of this attic?

When you say "there will be water and gas pipes running through the rafters ", I will assume you mean thru the bays or voids between the rafters, and not actually drill holes thru the wood framing that is the rafters.
Final Purpose - just empty space for insulation. May store some boxes up there if there if I can find room. No plans to drill through the rafters for plumbing pipes (generally speaking).