I'm about to start installing hardwood flooring and noticed that at one end the wall is 1" longer from one side compared to the other (10' and 9' wall to wall). What is the best way to correct this out of square wall when laying the flooring?
Well, you can't do much about the wall, so you'll have to deal with it on the floor. You've got two good choices. If your planks are perpendicular to the out of square wall, each run of planks will just be a bit longer than the last. This is the easiest solution.
Otherwise, if the planks run parallel to the out of square wall, strike a control line down the center of the room and work from there. It will mean ripping the last runs of planks on both sides of the room. It'll look fine when the base is down.