Walls are built using the same 16" on center layout as with the floor. When laying out for the walls (both exterior and interior) it's important to 'stack' the studs over the floor joists below. This is not only the strongest way to do it in terms of load transfer through the house down to the foundation; it also gives things like HVAC trunk-lines, cold air returns, airducts, plumbing and plumbing drain lines...etc. plenty of room run straight thru the walls and floor without a stud or floor joist being in the way.

Start your DIY project off the RIGHT WAY with a ROCK-SOLID FRAME JOB!

GWA Woodworks - custom framing and carpentry 720-205-0989