...of my wife complaining, I finally agreed that we needed a king size bed. Mostly because the queen size bed has started showing it's age. She sent me a couple of links to platform beds (and even DIY ones). I thought it was a great idea and a way to save money by not having to buy the box springs (2 on a king size).
Since a King Size bed is 76x80", there was NO way that I could create it as one piece. Not to mention how heavy that would be. So, I created 2 separate pieces and screwed them together. I also created a base for it to sit on that would raise it 6" off the ground, so total to top of mattress would be 18" (as requested). She felt our current bed was too high.