That looks real nice. Good job.
If a helix won't work, how about an elevator system? Would take up less square footage. Didn't someone have an article on this, in an issue of MRP?
No basement in that ranch but with that room you can do alot of railroading in HO dont listen to the EVIL N -scalers lol
Ahhh ... looking to move, too, and my trainroom could become a storage room w/rights to me ... about 10x8 ... plan would be 2 levels w/grades, no helix, yards on level 1 and semi-arid terrain above ... your planning s.b. valuable to me ... hope I can help w/thots, etc. ...
Of course, I'm N-scale ... do it, man, make the switch!