Astrohip, I'm with you on the shop. As mentioned by others, planning is really the key here. When I built my last shop (24x40) I added an attached carport (10x40). The roof trusses just extended over the port. I wish that I had made that part 12' wide as I park my pickup under it and opening the doors one has to be a little careful. Didn't think of that! I originally had considered a metal building, but thought better of it. The reason for that is I knew I wanted a finished interior (and well insulated). As a result, I concluded it would be cheaper in the end to go with a wood framed building. I like your thinking on the second tier floor for storage for part of it. I have been to Houston and minus your humidity we have very hot weather here in Northern California. I used 2x6 wall construction and it didn't really cost that much more than 2x4. Obviously, I got more insulation in the walls and the overhead is R30. With a swamp cooler (evaporative) I can keep it pretty comfortable. With a 200amp sub-panel I was able to run many 20amp circuits because I had the space in the box. I also had lots of panel space for welder, compressor, etc. circuits even if you don't plan on having 200a, you still have the panel room for expansion. Outside outlets are a must and I wish that I had put a 240v/50amp plug outside. I ducted airlines from my compressor using 'PEX' water lines for remote air connections. They will handle 600psi with no connections like PVC pipe would. Water is a must, even if it is just for washing up. A toilet is something I wish that I had included as the nearest one is 150' away at the house. I have a roll-up door that is only 10' wide by 8' high, but in my case serves me well. It's a chain drive and was only about $650. I pre-wired for stereo and speakers. The walls are 9' and the interior pitch of the ceiling is a 5/12. This gives me plenty of room to flip materials over w/o hitting the lights. I put in a ceiling fan (like a house fan) to bring the heat down in the winter and circulate the conditioned air in the summer. I have a wood stove. I have a dedicated room to store my tools (left over from being a general contractor) and an office. The office has internet connection and what you would find in any office. One advantage to this is I am able to secure this space against theft (gun safe, etc.) and keep out airbourne contamination from welding, wood and grinding. I didn't want too many shelves in the main space. I like having my shop tools on casters as I can easily transition from wood work to metal work. This gives me maximum flexibility considering the space. My welding table (4x8) is on casters as well. I have a rolling 6x6 verticle canvas covered tarp that I use when I need to grind or cut metal so sparks don't get into trouble. I added a couple of rainbird spinklers to the top of the roof as well. I always advise anyone thinking of doing a shop to add at least two future conduits to their panel that lead to the outside. It's really hard to anticipate what you will want to do in the future and it's so much easier now. An example is I added a ground mount electric solar system a couple of years after building the shop. It would have been so handy to have those conduits in place and cheaper. I didn't follow my own advice. Who knew? Anyway, my intent isn't to brag about what I have, but to give you some food for thought. It's funny how it works. You think about what you need and as time goes by you want more because it's such a great space. If you have planned for the changes it's a lot easier to do. There is nothing wrong with waiting to do things later when you have the coin, but a lot easier if you have made provisions for it. Oh, and don't scrimp on the concrete apron outside your shop. Also, make sure you have an understanding with your concrete contractor that you expect a level and uniform floor. Don't hire the cheapest guy unless you are sure you will get that floor. You will have to live with it. Good luck and I hope that I have given you some ideas!
