Here you can see the glulam beams we installed to carry the load of the new floor upstairs. The existing first floor ceiling-second floor was woefully under framed, with 2x6 joists spanning over 12 feet. By staying with short distances between the new beams we were able to reuse most of the beautiful old Douglas fir 2x6 joists. We needed a few new joists since we changed from 24" on center spacing to 16", but not many.

In the lower right corner of the photo you can see the original center stairwell, one side of which now carries the new ridge.