The most unfortunate feature of our house is (now was) the long, dark hallways. The one in the basement is 3 feet wide, 27 feet long, with a 7' 4" ceiling height. The main air ducts run right above the ceiling, and the outer wall is a central load-bearing one - so there is no changing this.
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As the diagram shows, we are getting rid of as much of the hallway as possible and turning it into storage closets.
Here is a picture of the hall before the remodeling started. Its about as claustrophobic as you can get as still meet code (at least in the 1970's)
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Before doing any drywall removal, I like to draw the full layout on the wall with a sharpie. I mark all the existing studs, as well as the new positions. This gives me the chance to make sure everything is going to land where it should. In this case, I moved the closet door 2 inches toward the bedroom door to maximize the room for the bed. A little extra time saves a lot of work later...
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I have learned the hard way, do not just start cutting into the wall. I like the reciprocating saw as much as the next guy, but there is pain involved in cutting things you don't want cut. I took my hammer and knocked a channel on the sheetrock, so I could inspect what's in there.
If everything was perfect, there would be no electical wires where I want to put the door (fat chance). In this case, there were two wires, both part of the same circuit. All I had to do was move it over one stud bay. Anything more than this, and I would have had to peel a good deal of the wall back to reroute the circuit correctly.
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Here is the framing in place - not a lot of work.