The front shade on the windshield really won't block the heat, only the light. Depending on how you're oriented the sun will head up the side windows pretty quickly. Lots of tricks, buy a dedicated windshield shade like a Magnashade, go to Lowes and buy the foil coated bubble wrap insulation, cut to fit windows, or get UV blocking tint put on your windows.
Summer heat is a problem for everyone due to the big windows, with a little effort you can cut down on outside heat and make your coach more comfortable.
__________________
|