If your roof is not shaded by trees, a light colored roof makes a huge difference. This can be accomplished a number of ways. Replacing your roofing material with a lighter color is ideal but expensive. Coating it with something like Henry Tropi-cool is durable but the product is also a little pricey. The absolute budget way to do this on an asphalt shingled roof is with a slurry of masonry lime. I’ve experimented with all of these methods and the results are dramatic. In my case the coating paid for itself within one season and made the house noticeably more comfortable.