In the two places I've lived with such an arrangement, some investigation into the original floorplan has revealed that there's been either an addition or some remodeling going on. And people just took the easy way out and slapped a new room on right next to an existing room, without bothering to add a hallway or the like. In my grandparents' house, you had to go through their bedroom to get to the upstairs bathroom, which was, for a time, the only bathroom in the house, other than a toilet in the basement. The house was built in 1865 and the bathroom was originally a closet. It was the only space for a bathroom. That is, until my grandparents had 7 kids and took the smallest bedroom and made it into a bathroom. They also made a pantry off the kitchen into a powder room, to get a downstairs bathroom. My brother and SIL have a child with disabilities. They needed to either buy a wheelchair accessible house or modify the one they owned. They looked at many houses that had been remodeled for handicap access--SIL was appalled, really, at some of the remodeling. She said it was clear they just added a ramp where it was easiest and threw on extra rooms where it was easiest to expand the house, without any consideration of the flow of traffic through the house or how the rooms would open up to each other, or even trying to match the style/ finishes of the original home with what was going on in the addition. She mentioned bedrooms opening directly off the kitchen, or off the master bedroom, or just a section of the family room walled off to create a room. In one house, they punched through the dining room wall and added a bedroom/bath right off the dining room. And another where they enclosed a porch off the kitchen to make the accessible bedroom, so everyone entering the house walked through the accessible room into the kitchen, unless they used the front door. Which no one does in farm country. They ended up hiring an architect to add on a wing to their house--you can't tell where the old house ends and the new wing begins. They did end up with a dining room with no windows, but it has two sets of french doors opening into rooms with tons of windows and sunlight and you really don't notice. They paid extra to get the addition done right, but I think in the long run they have a house that doesn't *look* handicapped accessible and hasn't lost any resale value.

What are you doing with those bedrooms? Are you thinking about selling anytime soon? My spouse has allergies, so we like a hard surface in the BR. In your case, I would put something in that matches the Pergo floors. (I agree that stuff holds up great. My mom put it in her bathroom 17 years ago. She hated it when it was installed, but it looks exactly the same and has not aged a bit). However, for secondary BRs, I'd tend to go with carpet. These are often children's rooms. The carpet gives them a soft surface (kids are always on the floor) and helps with noise. Unless you are doing something else with those BRs.

What did you do with the other twin? Do you have friends from college who come to stay? If you still have the other bed, there's the option of putting the twins together and treating it like a king. Get an inexpensive headboard from Craig's List or make your own out of plywood and fabric. I forget what the stuff is called for padding, maybe batting? You could even just nail the covered headboard it to the wall to keep it simple. Or use the twin sheets on the beds but push them together and just dress the top as a king. Separate them or not when you have company.

I'm reposting this from the OP's original thread as another option. The OP sent me the plans and I played around with them a bit more. I understood that she couldn't really change the exterior except for the bump out where her bathroom was. I got rid of that and moved it in so the width is the same but without the bump out in the upper right corner. She has some real concerns about this version and isn't sure she wants to give up some things as she'll comment later. However here are the changes I made: I made the hall a straight run from the foyer. No more maneuvering around a jog. Bedroom 1 is the same size but now the bathroom for bedroom 1 is next to it as opposed to having to walk across the hallway. I didn't put it in, but there could also be a pocket door from bedroom one into the bathroom so the au pair wouldn't even have to go into the hallway. However now at least it's right next to the bedroom. Also now there's a window in the room. I moved the laundry to the other side of the au pair's bedroom. This room now has a window and also now has a much shorter run for the dryer. In the laundry the cabinets opposite the washer/dryer can be used not only for additional storage but also as a broom closet and linen closet. I flipped the master bedroom to be on the living room wall. The master is now a foot shorter (but still deep enough for a king sized bed and a dresser on the opposite wall). My thinking was the living room has cabinets that would help block any noise and now the master bathroom and the master closet will act as noise blockers between the boys bedroom and the master. The master toilet room became a bit narrower but is still about 37-38" wide. If the OP doesn't get a 6' tub they can make the shower a bit longer. The boy's bedroom is the same size as before and while I don't love the idea of a bathroom taking up a corner, I couldn't figure out how to put it between the boy's bedroom and the playroom without losing too much space. The playroom now becomes a separate sanctuary where the boys enter their bedroom from the playroom. The problem lies in that now the playroom is smaller. I'll let the OP add her thoughts. bardzil, had suggested to me concerns about turning the plan into a four bedroom house instead. Here is my suggestion for if she ever wanted to turn it into a 4 bedroom house. However the smaller playroom is still an issue but then again living where she does, I'm guessing the boys will spend lots of time outdoors? (In this version, I didn't add in the window changes.)