If you hire a PE or LA familiar with residential construction, they'll be able to guide you around many pitfalls. Depending on where you live, it could quite possibly be required to get your building permit.
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"...students of traffic are beginning to realize the false economy of mechanically controlled traffic, and hand work by trained officers will again prevail."
kruzie,
Over the long haul, building without an Architect or an Engineer will cost you a lot of extra time and money. I hope that you don't learn this the hard way.
Best regards,
The answer depends on what species of wood you are using and the grade. Where I live, we use southern yellow pine and if you consult the Southern Pine Council webpage(
assuming a floor live load of 30 psf, 10 psf dead load and using a No. 3 grade, and a spacing of 16in O.C., the maximum length you would want to use is 12'-2". The Southern Pine Council design tables tend to be conservative, so I would round that up to 13 feet.
If you are using a different species of wood, consult your local lumber yard or Home Improvement store. they often have tables for the species of wood they sell and its applications.
It depends on what you are trying to accomplish. If you want to tile the floor or put hardwood down, the tile industry as well as the wood flooring industry recommend 16" spacing with a 3/4" tongue and groove sturdifloor plywood.
If you want a less expensive option, you can cut some corners and go to 24" spacing and expect some floor shaking.
