Started talking with my local PB guy who everyone has recommended to me. He's given me a couple quotes on two different size pools... 20 x 40 and 18 x 36. He's saying i'll get about 700 sq ft of actual pool with the 20 x 40, and 550 sq ft. out of an 18 x 36 freeform. How do you figure square footage on certain designs like Lagoons? I found a Lagoon shape that i like online. It says it measures 20 x 40 x 31. I've asked my PB guy about different freeform designs and he said the design does not matter as long as i stay in the square footage envelope he quoted me. I know how to figure square footage on basic shapes, but this Lagoon style, i'm confused? Help anyone? Here is the link to the picture i found. This is a fiberglass pool i believe, but i'm wanting to do concrete in this design if my budget allows for it.