This is a test of commonsense. Complete the next sentence:

How to frame a floor
Look up the building code for your area.
Your city will have building code, or basic requirements that homes and buildings are required to meet. If your floor isn't up to code, you might get fined and will probably be required to pull up the entire floor.
Know what the code is for your area before you start, because it can affect everything from the materials you need to use to the measurements you use. Your area might even require a permit for a floor to be considered up to code! Plan your floor framing layout.