Structural fiberglass is quickly gaining in popularity for use in pergola kits due to its durability and ability to accommodate many design options. A process called pultrusion gives the fiberglass pieces unparalleled strength. Because of its strength and light weight relative to other materials, it can span farther with fewer posts. A proprietary color coating makes it possible to make your fiberglass pergola in virtually any color you choose. Resistance to heat makes it an ideal choice over outdoor kitchens. Rafter and purlin spacing can be customized to allow for just the right amount of shade. A lifetime warranty is also offered.