Very nice setup! That is exactly what I’m trying to build over my beds this year. Only difference is I will be building mine On uneven rock slope lol how tall are your hoops? And what length did you cut them? If I may ask. I’m thinking i need around 25 ft of pipe per hoop. Am aiming for 10-12ft wide by at least 7-8 high, hoping it will be higher than that. Also, what thickness pipe did you use? Will 1/2 inch be ridgid enough? If I have to I can put in a ridge pole out of wood for support along the top to help support...
Each length of tubing is 10' long from the store. The first year we made it, we just connected 2 lengths to make one loop. The next year the plants grew so tall we added extensions on both sides which was very easy to do but we also had to increase the height of the wood frame on each end as you see in the picture. This is going on 3 years of that tubing being outdoors through snow, sleet, 40 degree celcius weather and windstorms and it's as strong as it was day one so don't worry about it aging on you, especially when you consider that the tubing is actually extremely cheap and even if you have to replace it every 5 or 7 years the cost is insignificant.
The height of the first version we made with just 2 lengths of tubing connected together was 10' exactly. We added extensions the next year to make it closer to 13' tall. I also added a wooden brace along one side that gets all the wind. It got hit with extreme windstorms a few times and because it was so flexible it withstood it all. My greenhouse is about 12 or 13' wide and 15' long. So 2 of the 10' lengths made a greenhouse that's 10' tall and 12' wide basically (keep in mind that 2 lengths of tubing made a greenhouse 10' tall and 12' wide but each piece started about 3 or 4 feet up the wooden frame as you can see in the pictures). Along the 'spine' along the top of the greenhouse we attached each rib to one another by using a 4 sided connector. This was necessary to get rid of most of the sag. You could also just add a wooden brace in the very center with a 10 or 12' two by four.
I used 3/4" pvc tubing. If you try using 1" it won't be flexible enough. 1/2" tubing is too flexible to offer enough support. I can take a few more pics that show the fasteners and connectors I used if you'd like. I used it to make some covered beds along the back patio too as you can see in the pics. Once I got started making greenhouses with pvc I couldn't stop! There's a bunch more pics anyway, hope that helps.