How to install a flush laminate beam?
We're rearranging our upstairs walls a bit to add a bathroom between two bedrooms. Here are the prints. Note the dotted line, which is the current load-bearing wall.
The prints call for it to be replaced with a flush laminated beam, which, if I understand correctly, means putting a beam above the ceiling, suspended from the joists on either end, and then hanging the floor joists of the room above to that beam.
We're DIY-ing this, so want to make sure that we're executing it correctly. We've pulled the drywall off the LB wall, and it's just 2x4s. Up in the attic, the joists are 2x6s spanning the "new bedroom" and 2x8s spanning "bedroom #3", and they intersect and rest on the 2x4 LB wall. Here's a photo showing the intersection above the LB wall. The board in the lower right is just the frame for the attic access panel.
And here's a couple shots of the attic. We want to eventually finish it into a 20x20 room, which will require beefing up the floor joists to 2x12s.
So back to the laminate beam. Our thought on how to install it is to build the 2 outside bathroom walls to provide temporary support for the joists. Then climb up in the attic, cut the joists off so that a beam can fit between them, hang the beam to the joists on the outside wall and the inside wall, then hang the just-cut joists to the just-installed beam.
Are we in the neighborhood here, or completely off-base?