Brettski,
This building style has two big strengths to it. A big storage/workshop area and a decent apartment sized living area. Both can compliment each other and increase the value of your land. This is what I like about it.
You can build it any way you want, but there are ways of throwing money away on a home that when you are done building it, you realize what you've done. A good architect/designer or builder will recognize these things and either not do them, or steer you away from them. The clear span is one of those things that is screaming out, LOTS OF MONEY!!! without any real return for what you will spend.
Having the living quarters in the middle of the span increases the load on that span and of course, increases what you will have to pay per square foot to build that living area. When building, price per square foot is king. You can really mess with this by making it complicated or you can save a ton of money by keeping is simple.
For what you want, or at least, my interpretation of what you want, look at some layouts of single wide mobile homes and Park Model Trailers. They have width restrictions and smaller square footage, which is what you are looking for. Instead of trying to reinvent the wheel, copy from the experts who have been doing this for decades. In those designs, you will see that they don't waste any space, and take advantage of every square foot. They are under tremendous pressure to build as economically as possible, so the design lends itself to this. Ignore what materials they use or how they cut corners in their build, that won't apply to you. Just look at their layouts. How they put the bathroom and plumbing in there with the mechanical's. Where storage is located and the flow of the rooms. When done right, it's simple, straight forward, strong and affordable.
Think of it as a two story build with the living quarters on the second story. The bottom section will have the supports to hold it up on the posts. You can make this fairly tall to allow space to park a tractor or create a workshop. I would go ten feet as a minimum, with 12 feet being ideal. Then add the wings to either side for a huge amount of storage.
You don't need concrete for any of this upfront, it can all be built pole barn style and last long past your lifetime. Or you can pour concrete footings for posts and go that route. Then when you have extra cash, you can pour concrete. Do all of it, or do it in sections. It's a huge upfront savings of your cash or how much you will need to borrow.
The actual building should be in the $15 a foot range to make it weather tight. Then the real money can be spent on how you finish it out. Here, you can take it to any extreme, but with a roof over your head, there's no rush. I know people that have been slowly building their homes like this for ten years or more. Every year, they finish off something. A little here, a little there. They do it all for cash and never stress out over when it will be done.
Write down a list of what you need to have for the living space.
Two bedrooms. Master with a nice sized closet for one, and the other just needs a bed or bunkbeds for guests.
Full bathroom or 3/4 bathroom? Maybe a half bath downstairs for when you are working on a project. A sink downstairs is a must at the very least. With one bathroom, it needs to be in a common area. A half bath is always a nice extra if you have the space.
Kitchen - Think counter space and an open design incorporated into the living room.
Dinning/eating area isn't really needed. To maximize the space in my home, we didn't put in a dinning/eating room. We put in a breakfast bar in the kitchen and some bar stools that work great, but mostly we eat our meals in front of the TV.
Laundry - a closet with a washer dryer combo work great for this
Mechanical room - Use the space downstairs in the shop. The water heater and HVAC system will work great down there. Take advantage of the space for your ducting and plumbing like done in most homes up North with their basement. Same concept to save on space in the living area. Don't put anything in your attic space so you can maximize on insulation.
Closets. Don't think that you can cut corners here. They are very important. The longer you own the place, the more you will wish they were bigger. Jackets that stay there year round, vacuum cleaner and brooms all need a home.
Fireplace and wood storage. With this plan, you can keep a chord of wood inside and out of the weather if you wanted. It also give you more flexibility how to run your chimney.
Stairs. Two options, outside and inside. With the deck that you want to have, outside stairs make allot of sense. But with a huge storage area, parking area and workshop under the home, inside stairs would also be nice. Having both would probably be an expense that you would appreciate over the long term.
Think of how you will move furniture into the living area when laying out your floor plan. I've taken out windows on homes to get stuff inside of them. A good plan will address this.
French doors are nice in other peoples homes, but a pain to own. They are terrible at energy efficiency, cost allot more then regular doors and don't have the same security of a single door. One glass 36 inch patio door with a wall of windows will give you the same look, but with more security and better R value then a french door ever will. Sliding glass doors just suck and I never recommend them. Those who want them usually change there minds after talking to those who have them, or searching online for reviews on them.
Once you get the floor plan nailed down, then you can work on the engineering and methods to save on energy.
If you are dead set on a clear span for underneath, then figure out the engineering and see what it will cost you to get it built to code for your area. After determining that amount, I think you might reconsider the clear span idea.
Eddie
