I started out with an overall plan of how I'd fill the room, including setting benchwork elevations and locations of key scenes. Once I engineered out where everything would be, I started with the most complex part, which housed some hidden staging on a lower level, and the main junction that would feed the rest of the layout.
I took all my measurements, laid out the plan in a scale drawing, and headed out to the workshop to start construction. The first phase was 3' x about 8', and started with an L girder frame I had salvaged from two previous layouts.
The staging level, with a one turn helix that would eventually connect to the rest of the layout.
Next I installed the scenery level framing that would cover the staging yard.
And went to work on the scenery bits.
Did the placements of major structures and tracks in the paper mill scene that would dominate this part of the railroad...
and even installed the scenery base. All out in the garage. It was handy to do this, because once it got installed in the attic, it would be near impossible to reach the areas that would end up in the back under the sloping roof.
It was also nice to be able to tip the frame up on its side to work on the wiring underneath. No hot solder fell in my eyes on this project...
Here it is the day it was ready to haul up the steps. This shows the back of the frame that would be against the wall when installed.
And here it is in place, ready to begin the next stage.
Finally, once I had the room renovation complete, a friend came over and we hauled the first section up the steps and into the train room.
I continued to work on this section while I worked out a temporary track plan that would at least allow me to run some trains. I added some elevation to the scenery that I couldn't do out in the shop, because it would have made the section too tall to bring up the stairs.
Eventually I built this peninsula to close the loops and create a basic layout I could run trains on. The lower tracks connected to the staging yard.
Eventually I connected the loops to a temporary yard, and ran a line around the room on a narrow shelf to connect to the staging yard.
This junction tied the yard lead to the layout.
and the yard, temporary though it may have been, was tricked out with a little engine terminal and scenery.
I worked with this layout, even hosted several ops session, for a few years while I planned out the final expansion that became the finished product.
These scenes were all built on the temporary loops section.
Eventually I tore down all of the temporary stuff and replaced it with a huge yard, bigger and better scenery, and a more complete operating scheme, including a second large staging yard. Over all, it took about 10 years to get from the beginning to the day it came down.
The best part about working in stages is that all along the way I learned new techniques and skills, new technology became available, and I gained a much more thorough understanding of operations. Mistakes I made on trackwork on the first section were not repeated over the whole layout, and when I learned something new, I only had to fix the parts that were already done, not the whole layout!
The one thing that was critical, though, was to make sure my wiring was clearly labeled and color coded, so as I changed things up I didn't have to climb into the rat's nest and do it all over. Make sure you set up a clear system for that, and stick to it. I had separate circuits for track power, turnout control, and scenery lighting.
Eventually I added DCC turnout control along the main line, so I had to change up some things, but having a system to follow made it easier.
I hope this helps you think through your project. Basically, start with a critical junction or other section that will be an epicenter of operations, trackwork, and details. Then let the rest of the layout flow from there.
Lee
