No I will use cattle panels on top of 6' walls. I will also use the silver top material we looked at while living down the road from a major greenhouse supply. I think the over all size will be 14' wide x 21' long. That's 5 panels and 2" shy of 21. We can grow herbs, tomatoes, peppers, summer squash year round. All those things have gotten very high here now. $2.99 a pound for plain red tomatoes now. Squash run from $2 to $3 a pound. We can heat one that size with one of those camping propane heaters when needed. We can also use it to start all of our own spring plants of the varieties we want and not just what the bit supplier has to sell.Will you use PVC as a frame for your greenhouse? How big will you build it?