I too am looking at a two level layout. Since moving into our new home, my HO train hobby is to be located in the third stall of a three car garage. I will wall it off and add HVAC to the room.
I am looking for some guidance on layout heights and access from those on this list who have actually done this.
In particular, what clearance did you leave between the bottom of the lower level and the floor for maintenance access? Also, what clearance do you have between the bottom of the top level and the top of the lower level? Would you recommend what you have or would you change it if you had it to do over again?
There has been a lot of discussion on valences and lighting but I would appreciate any new info on lighting the lower level of track.
I intend to use a helix to change levels and to double as an in-line staging track.
For what it is worth, I am 6'2" and 52 years old. I also have an 8 year old daughter who is mildly interested so I would like to keep the lower track at her viewing level.