Will be installing 3" x 3/4", oak, nail down in a long hallway with doors on both sides. The rooms behind the doors are carpeted. At some locations the oak will be installed between directly opposite doorways that have undercut transition boards in place but not yet fastened to the subfloor. Doorway transition boards are perpendicular to the hardwood that will be placed.

1. I prefer to route and spline the flooring ends to avoid butt joints at the transition boards. Am leery of my ability to keep the ends of all the flooring flush to be able to later slide the transition board into place with adhesive on tongues and grooves, firmly locking flooring to transition strips.

2. Have considered attaching transition to subfloor, then trimming flooring tongues/grooves where necessary so that last boards can be simply dropped into place. This would result in butt joint at transition and necessity of setting some flooring in adhesive and face nailing (which I'd like to avoid).

Am I over-complicating this entire process? Sure would appreciate opinions, suggestions, other options. Thanks,

Reg

If there are doors in the doorway you could make some small wedges that press the flooring an d transition strips down under the door when it is closed holding the flooring down until the glue has hardened so you would not need to top-nail.
Plenty of the right glue will keep everything in place.

I prefer option #2.....but no butt joints and the last board of each row gets fitted into the field of the row. This sounds harder to do than it actually is.
The new flooring will be run perpendicular to the transitions in the doorways. In that case you will be doing what is referred to as a 'net fit' between the 2 doorways. I find it easiest to cut floor boards to size and fit them somewhere in the middle of the floor rather than where they abut the perpendicular room doorway board. It's easier to get very accurate measurements in the middle of the floor. The 'net fit' boards i.e. those that will go in the field of the floor will have to be cut to size and have either a tongue or a groove added to the end of the board. On a table saw you would have to hold the board on end to cut a groove or hold it flat to cut a tongue. You could install it without a new tongue or groove on the end but this could be a squeak point. To do this technique, once you get to the 2 rooms lay the new flooring from both directions. Pick lengths so that will have a decent length board to infill to complete the row joints remain staggered. To measure the infill board, take another board and lay it against the current row and align its end with the end of the board in the current row. Take a long infill board and abut its end to the board in the next row so that it spans the infill gap in the current row. Take a straight edge and lay it on the edge of the end of the current row board on the other end of the infill gap. The straight edge should be perpendicular to the current row boards and extend across the long infill board. Mark the cut point on the long infill board.....this will give you the exact length the infill board needs to be. If you need a groove on the end just groove it and you are all set. If you need a tongue you can either make it longer and cut a tongue or add a groove and glue in a spline to create the tongue. This 'net fitting' will take some extra time as you will sneak up on the exact length. When you install 'net fit' boards push them straight in...you can use a longer piece of flooring to move them straight.

Appreciate the responses - adhesive and wedging plus the "net fit" explanation.
Have been using splines and flooring router bit at various locations to avoid butt joints and change direction of flooring. Prior to Net Fit explanation I was really scratching my head as to how to continue. Thanks much.

Reg