The attic is a very nice place to grow, depending on how much room you have. You can grow wonders in there, with the right light the heating should be fine without a cooling hood, slap a fan in there to strengthn the plants stock and stems.

Make sure you do a thural clean up in your attic before you even turn your light on, there is alot of easy things that can catch fire in a blink of an eye when the light is hot.

Goodluck.