Los Angeles-based designer Ben Solemani, born into a family of rug experts that runs four generations deep, is the founder of Mansour Modern and the designer of an extensive collection of rugs for RH. We talked to the designer about his tips for picking out the right rug—from choosing practical fabrics to knowing how to spot pieces with staying power. Read on for Solemani's advice, and check out some of his latest RH designs in the slideshow.

Covering ground: "It really depends on the room—some rooms you want to leave a foot and a half [uncovered] around the room, like in a bedroom. I like to show some wood. I don't like rugs too close to other rugs, and like to give enough room around them to show that they're special."

Materials: "Wool, the most durable [fabric], you can wash—but it depends on the wool. It's the most practical choice, it's plush, and it's very cleanable. Silk, with its softness and the luster, is elegant and beautiful. But it's not just the material; it's how it's made. You want a rug that looks natural."

Shopping mantra: "I always tell people buy the best and the nicest. Don't just buy. A rug that's good quality looks better the more you use it."

Timelessness: "I don't think any one thing on a rug should stand out; it has to have harmony. When you buy a rug, look for something that's not gimmicky, not something where half the rug has a design, and half the rug doesn't. Those you get tired of really fast. A beautiful rug with harmony is timeless."