I'm building a 12x24 art studio. The local builder wants to build on concrete piers (2.5 ft deep) with pressure treated wood posts sticking up. Soil would be piled back up against these posts. Although I will install a french drain around this building, I'm concerned (in inexperienced) that in time the pressure treated wood may rot - whereas concrete piers won't. I don't want to have to fix this 20 or 30 years from now, when I'm in my old age! I just want an economical art studio. Any suggestions? I've scoured the blogs already. Thanks!