Fiberglass Lath. In contrast to traditional metal lath, woven fiberglass SpiderLath is rustproof and unlikely to cut the installer. It’s also very light: A 300-square-foot roll weighs 23 pounds. Foam strips running the length of the product provide separation from the substrate and form a seal around nail penetrations. A 4-foot-tall 300-square-foot roll costs $160. SpiderLath, 870/725-3902, spiderlath.com.