In this recording setting summer of 2012 with temps hitting 5 consecutive days in a row already this month of July and a 6th consecutive day tomorrow its worth to check into Radiant Barriers. These radiant barriers are under various names such as thermal shield, attic foil, radiant guard, radiant barrier,etc.
Checkout the link to see more info about radiant barrier technology. This technology coupled with proper attic fan or solar attic fan will definitely increase the efficiency of cooling your home and add life to your roof tiles as well.