Our old (2005 September) greenhouse is falling down. After investigation most of the south side joists were totally rotted out. We did a critical evaluation and came to the decision that it was not repairable. Instead we would take our 10×10 cloth shed (whose roof only lasted 2 years), tear away the material and use it to build a greenhouse with plastic walls.
We located it in another place, but this was a little low spot.. so we added a yard of dirt to raise it up.

We then put down about 11’x11′ of weed barrier and some gravel along the edges to hold it down.
We hope to reuse some of the walls of the old greenhouse for ends of the new one. That and the plastic which ran about $100, a spare screen door.. we should be ready for construction in a few weeks.