>>1695150For longevity a glass greenhouse will be better. They are mostly build-once and forget with only marginal maintenance if properly designed. For cheapness and faster building time a plastic film greenhouse is what you'd want. That plastic film will need replaced every 5-7 years depending on its durability and UV protection. No UV protection and it probably won't last 2 full years. The framed plastic panel greenhouses take about as much time to build as the glass ones since they just replace glass with plastic. The plastic panels still degrade over time and don't allow as much light into the greenhouse as the glass will. The plastic panel greenhouses can be better insulated since you can buy panels that are multiple layers, though that reduces light in the greenhouse with each layer. So, that is a trade off.
Personally, I'd build one with two layers of glass using old windows/sliding glass patio doors and treated lumber with masonry foundation. While a nice poured cement floor would be great, you can get by with gravel.
