ok, you asked for it:
(you dont mention, but i assume you are going to work on vehicles in here. some of the comments i make really only apply to that.)
1) as someone noted on another thread i just read, make sure to site the building so that you can see all the doors from the house. this helps you to make sure everything is closed (and the lights are off).
2) i think that the building either needs to be substantially wider, or it needs to be two bays. the way it is configured there is little room between the vehicles and the sides, or each other. while OK for a garage, if you are going to want to open the doors, and work around it, you need to leave room. if you are going to expect to put storage or tool chests on the sides, you need to allow for that. i am working on a 1966 pontiac. i have three gladiator 8'X2' shelving units, and they are pretty full of stuff i have taken off. if i had the room, i'd get at least one more. room for storage of larger things, like hoods, or transmission jacks, or sheet metal brakes along the sides might be useful too. and dont forget the tool chests. currently i am working out of three 26" stacked boxes, along with a few cabinets for things like drills and other larger tools.
you will also need room for a workbench. somewhere spread out the parts of the transmission as you work on it.
3) i dont think it is tall enough. i would want at least 14' at the back, sloping up towards the front, if that is how you want it. if you get a lift you will need at least that much space. and i am talking about clear ceiling height, not outside building height. i assume that girts refers to the joists you intend to use to support the roof. your drawing doesn't indicate if you intend to just run unsupported from the front to the back, or if you intend to run beams across at the side posts, but unless you intend to add a grid of support posts in the middle, i dont think that you will be able to get the lengths you are interested in without them being pretty thick.
4) while i am sure you are thinking about electricity, run an additional conduit for "phone and data". nothing beats putting an old PC in the shop, so you can watch a youtube video of someone (or several videos of different someones) doing something you are preparing to do, or looking up parts you need online. it will also be useful if you get into that "streaming music thang" (which i am not).
i am using an existing space now, but if i decided to build something, and i have thought about it, i think i would start with a floor plan. layout where everything goes. car locations, work spaces around them, tool storage, car part storage, workspaces for things you remove to work on, things like that. consider where you want power, including ceiling mounted boxes.
i like to have circuits for lights (switched as you see fit) and separate circuits for pull down power cords on the ceiling. i use 4' shoplights, which come with an attached electric cord so that they can just be plugged in. i bought LED lights, which were more expensive (about 40$ per fixture, as opposed to $15 for fluorescent lights) but i could put a lot of light out without running more circuits. of course, if you go with the "plug in, hangs from two chains" light, you can replace them later pretty easily. i
you want power along the walls, and dropped from the ceiling in the middle. i feel that you cannot have too much light, or electricity being too convenient.
if you reversed the roof, and had it slope up from the front, you could add a loft in the back, since you probably won't need more than 9 feet of clear space at the back. and go with 9, you would be surprised at how many times you will hit the ceiling if it is 8 feet. this will also allow the lights at that end to be closer to the floor, and you can even recess them between the joists. a loft can add valuable storage space for things you get that you dont need yet, like replacement parts or fancy upgrades that you want to protect from the garage environment.
and, finally, make sure you deal with the water. that roof might shed a lot of water, and you want to make sure it doesn't come into the shop. making your "floor" height a few inches above the outside grade will help. if you are cutting into a hill, run some drainage pipe, and put some gravel around it, as deep as you can get it. it might be worth putting a few drains in the floor, leading outside. be careful though, the town might have an issue with the possibility of oil or something getting out.
there, that is enough, for now at least.
you did ask . . . . . .
stev
