I'm mostly an imager and from home I typically do narrowband because of the light pollution so I don't need to be in the dome. Plus the best spot for the observatory is near the front of our backyard and the HOA would have a fit about it rising over the fence line being that close to the front of the house.
So I've decided to make a VERY small dome. Essentially the bare minimum required to fit my equipment and give me a tiny bit of room to grow (very tiny). The diameter of the dome will be 5 feet (1.5 meters). And the entire structure will be around 6 feet (1.8 meters)tall. This keeps it just under the fence line and out of the HOA's control :-) The diameter of 5 feet was chosen for a couple of reasons. First, I'm planning on using a gore type construction with 1/8" masonite for the dome. At 5' I can build the entire dome from 2 pieces of masonite. I also plan on fiberglassing the exterior and possibly the interior of the dome as well. This will give it added strength as well as weather proof it. Second, at the smaller diameter I should be able to lift the dome off if needed by myself or with the help of one person. Since it will be unlikely that I'll be able to get into the dome (at least not comfortably) I'll need a way to do periodic maintenance and access the equipment.
I initially considered building a roll off roof as I could lay the scope on it's side and make the entire setup even smaller. But where I'm at is fairly windy so the added wind protection of a dome is a nice plus. And I like building things like this so the challenge of building the dome was a big part of the decision as well...one which I may regret later!
I'm also planning on automating the dome (eventually). Initially the azimuth will be automated but I'll likely forgo automating the shutter until a later time. I plan on building all the control hardware as well and writing an ASCOM driver for the dome controller. I believe there is already an Open Source Dome Controller out there so I may check that out as well.
Attached is an initial drawing that I have done with a G11 inside of the mount for reference. Everything is to scale to give you an idea how small the dome is.
Hopefully I'll get some pictures of the actual dome construction up fairly soon. I'm headed to the lumber store to pickup materials to start on the dome here shortly.