This canopy is meant to protect the garden from the heavy rain and hail we often get in Nebraska. It also cuts UV and does help with noon day sun. So far there seems to be enough ventilation to prevent any extra heat buildup under the greenhouse tarp.
I started with some cheap T-connectors I already had from Amazon (before I found MP), u-bolts and some recycled parts from a gazebo that was destroyed in one of the storms. The gates are recycled too - we try and recycle as much as we can.

The first attempt had a flat roof and was built with 1/2 " EMT. Since it was just a shade it would be fine. Thought there was enough pitch water would run off but as soon as it got a little water on it it sagged and made a bowl. It held an amazing amount of water without breaking but ,cam very close to disaster.

Decided on a redesign to pitch the roof and beef it up. Still used some 1/2" since I already had it but added a 3/4" ridge pipe. So I did more research and found Maker Pipe I got the 135% connectors for the roof. So far it has survived a couple of storms and it's performing well.