If you have any doubt about how much roofing and siding affect your home’s appearance, ask some kindergartners to draw a house. They always delineate the roof and exterior walls first, then complete the picture with doors, windows, and a big smiling sun. That’s a real lesson in the basics of rejuvenating a house. “Get the right combination of exterior products, and you’ll turn an average-looking house into something stunning,” says CertainTeed Corporation spokesperson Mike Loughery.