I just had to do this when I was rebuilding my boat dock. Looked around the internet for ideas on gazebos and took a little from here, a little from there, a lot of "by gosh and by golly".
Not nearly done yet, but I have the rest of summer to finish it. Hopefully, the hard part is done. As you can see, there is no lateral support for the roof. I had a hell of a time figuring out how to put those rafters up there so they would stay. Finally had a brainstorm, and constructed the center octagon of 2x8's and lifted it with a drywall lift until I could cut and fit all the supporting rafters.
Cutting all these compound miters has given me fits! Some boards I've cut two, three and one even four times before I got it right. You can't imagine how complex this project has been so far. It is very easy to get turned around on angles.
Next the pagoda roof will go above the main roof, then a cupula to top it all off. I plan to use cut cedar shingles ($417 per square) since they are lighter and will add structural strength to the roof. Being on the lake, we experience a lot of wind, since there is nothing to stop it coming across the water.
I'll update this as I make progress. The wife says it must be finished by October for her class reunion in the back yard.
This has definetly been the hardest project I've ever tackled, harder than the Windsor chairs I am accustomed to making.
Okay...You've all been warned.........Don't try this at home.