Nothing special. 6x8 and then a sloped glass roof between 7-8 feet. Built with old windows salvaged from a massive ocean front home renovation. Sun room windows. Moving them was a bitch but it turned into a great set up.How big is the greenhouse?
The feature is the THERMOFOR window vent installed in the roof. These things are the bees knees. Some European invention (I think), as it gets hotter, the lever expands and opens a window more and more as it heats up. You can adjust them depending on needs.
I would like to expand it but have been holding off with the 'better half' talking about wanting to move. One can be pretty productive with not a ton of space in a green house. Great for starting your own seeds and then transplanting them into the garden. Great for specific vegetables - peppers, tomatoes (I just do the bush variety in it due to its size).. basically veg that are heat and sun whores. Good to drag the potted plants into early in the season on rainy or cold nights.