To a large extent, this choice will be influenced by the type of covering material chosen, the desired permanence, and costs.
*Wood: Be sure to purchase treated lumber for exterior use.
*Metal-framed: Aluminum or galvanized framing lasts a long time with little maintenance.
*Schedule 80 PVC pipe: For small Quonset-style greenhouses that are to be covered in polyethylene, but PVC requires extra support to withstand strong wind.
