Thanks. After looking at all the plans I think I would like to keep it simple and start out by building a giant 24' replica of the dome featured in the book. but have it lay in the ground instead of hanging over the pool. I would have to buy a 40 by 100 foot roll of plastic to cover it for 200 dollars that would be enough to make two domes and it would cost about 120 dollars for enough 1 1/2 inch PVC per dome (two crosses, eight three ways and 12, 20 foot lengths of pipe per dome). Probably no door at first, just lift up the plastic to get underneath and see how it turns out and if I use it. If I like it I will build another one and get fancy with it. Also I will probably add a ring made of 40feet of 3/4 pipe over the dome for added stability.