hey there, i'm wondering whether anyone out there has been involved with designing large diameter octagons. specifically, an octagon with a 24 to 30 foot diameter, unspecified roof pitch. i realize this is a large span for clear span framing, but the design needs to avoid a center post that reaches to the floor. on the smaller 24 foot end, it seems like a clearspan with a king post would be the way to go, but on the larger 30 foot end, there could be posts supporting the rafters eight feet or so in from the perimeter posts. design feedback would be appreciated, but i'm also wondering if there are existing plans for a structure that meets this description out there for sale. any leads would be much appreciated. thanks