u/benjilove-art

I am installing new 3/4'' hardwood across the 1st and 2nd floor.
Subfloor is 3/4'' thick, 4'' wide planks screwed on the diagonal + plywood on top, so not too concerned with floor joist direction (or should I be?)

https://imgur.com/70zTPma
Pros/cons

Vertical - I don't get weird 3' planks next to the stairs as it will run lengthwise

Horizontal - aligned with all windows, but does not run lengthwise next to the stairs so I end up with short planks in the hallway.

1st floor is installed horizontally as the hallway dictated the direction, if that changes anything.