seeking just the right amount of wrong

First let's get a couple of points out of the way.

The interiors in no way fit inside the Roci model. The set designers have admitted this, because they have to create sets that a. look good, and b. work for filming.

There are a bunch of changes around Season 3. I suppose this could be explained as a retrofitting done on Tycho, which gives me the pleasant mental image of the boys writing up the most absurd wish list possible, and then being floored when Fred Johnson agrees to ALL of it.

None of the diagrams that people have made online are useful for the show. They're just very different. Books and film are very different media, and it would be miserable trying to shoot a TV show in a place that matches the book descriptions.

Are we good? Good. On we go.

I went through each episode and tried to grab screenshots of a couple of areas and anything that hinted at a layout. So my main focus was on the galley floor, the med bay(s?) and the bunks.

There is clearly no single ladder going through the center of the ship, because most of the ladders we see end on that level. I suppose it would make strategic sense in case someone managed to get onboard. Having a straight shot to the bridge would make defense a lot harder. However, I have still created a couple of gloriously shitty MS Paint diagrams. I've marked the orientation of the visible ladders/stairs on all of them.

Please enjoy.

The first thing I noticed is the writing on all of the frosted glass doors. Many of the crew quarters have these, but there are exceptions. There does seem to be a consistency, so it's possible they indicate the level.

Let's start from the top.

The armory and airlock is right below the bridge, and the door on the opposite wall from the airlock is labeled A2.

This would make sense if the levels start from the bridge and go down from there. However, there are no doors ever seen that have a "B." My thoughts were that it could be explained as a gap between the bridge area and the lower levels. It would make sense as a safety measure. Again, create a safety gap between key floors of the ship. They already have the "crawlspace" layer between the inside and outside walls where people are seen working a few times.

This diagram is constructed based on screenshots across the seasons, as well as the live walk through of the sets available on YouTube. Most of the doors on the galley level start with a "C" except for one notable exception, which I'll get into later.

The location of the lift is an assumption. In episode 2.1 Amos Tries to Moider the Saddest Man in the Universe, we see Miller leaving the med bay to go check out the coffee maker, and he enters from the left hallway. (This is also where we see the label "C4" on the door. There are zero indications what is inside any of these rooms, so this is a good place to get creative.)

"But Pants!" you say, "What about the ladder?"

Miller specifically doesn't take the ladder as he's leaving the med bay. Holden tells him to turn right and, while a director may have thought that the med bay would be on the same floor as the galley, there are no images from the med bay that indicate this is possible. However again,

Is there a door here? It looks like there isn't. But again, I'm presenting the information I gleaned, and I would highly recommend that people choose their own canon if they really care about layout. One way or another, you'll have to ignore something to make it make sense.

This is a bad shot, but I can confirm it's labelled "C6." Again, no inside shots.

The major outlier is the door across from the galley. It is labeled "D3"

Buuuut, get this. There's another door labeled "D3".

After Ganymede, when Naomi goes to talk to Amos, he's working on a level that looks different from the others. There's this small, liftish room that is labeled "D3." Logically, they may have just recycled the door for a minute to make a temporary set. If you wanted, you could say that they're on "D" level (since there's no other doors seen that are labeled with a "D") and the door on the galley floor is for the lift that goes to "D3."

But wait! There's more! When Holden comes to get Kenzo and we see through is augmented eye, the door behind is also labeled D3, which is where we get to the point where you have to ignore something to make it make sense. They were clearly using this door as a filler for temporary sets and you need to assume at least one is mislabeled if you go with my theory that there is a rhyme or reason to the doors.

There are no signs of any doors labeled with an "E." One could assume this is another gap floor, or that it has something else. Maybe Holden's coffee stash, or Amos's sari collection.

"F" is for... Fucking Shot Again? In episode 2.1, we see that the entrance door to the med bay is labeled "F4." This door is open in other shots, and there is a ladder right outside.

There is also a door on the opposite side of the med bay that is closed in every shot I could find. This comes back in S3.

Below that, the only doors for quarters where we clearly see the letter are labelled "G." First is the door for where the put Prax.

And the room where Holden holes up to try to get Miller to talk to him.

Alex: Uhhh... sir? Everyone is hitting on Amos and ignoring me.

Also, I just have to say that I appreciate that the Star Trek Red Alert Coloring is canon in The Expanse.

Now, this all seems well and good, but there are a couple of major changes seen at the start of Season 3. First, the med bay changes.

The entrance seems to change, as well as the layout. However, there is the open doorway that seems to lead to additional med bay, which would correlate with the door seen in the "original" med bay.

During the same scene, we see that the far wall has a large desk with monitor that one could assume would be used by the medical personnel. So my assumption is that the med bay is broken up into at least two compartments, which would be useful for quarantine. There are no other rooms show with the "F" letter, so the rest of the floor could be medical supply storage.

Second, there is a distinct change in the crew quarters, which leads to...

The Second Part of My Thesis, Upon the Topic of the Quarters of the Ship Once Known as Tachi

Please let me know if there is anything I missed or seems incorrect.