The most fade-resistant fiber, polypropy-lene, also called olefin (about 50 cents-$2 per sq. ft.), is often used in indoor-outdoor rugs. It's a decent choice for sunny spaces. The material cleans easily, though it also gets dirty more quickly due to an oily film that attracts soil. Polypropylene crushes easily—and permanently—so stick to low-pile Berber styles. Bottom line: Use it in a sunroom but not the family room.