Layering Up: A lot of pergolas will only have one layer of overhead beams say going in a vertical direction. One way of adding more shade and roofing to the pergola is to add another level of beams this time going in the horizontal direction as
Alfresco Cellular PVC Pergola - Alfresco dining comes with style and shade for comfort. This hollow vinyl pergola features square post caps and long, 2 by 8 carrying beams. The horizontal/vertical lattice side panels provide privacy.
As long as it doesn't look like a shower curtain the way this does. "Outdoor curtains are a great way to soften your porch and keep your patio furniture from fading, Just make sure that its treated fabric so the elements don't destroy them!