layout height is influenced by a number of factors. In a loft often the area available reduces with height as the roof slopes in. My loft layout was compromised by this and was a bit low best operated from a chair..
The bed layout is at what ever height the bed is, best viewed and operated while kneeling. The old bedroom layout was at around 60" with a 58" duck under height which needed a step ladder to do track laying etc but looked great to me when standing/operating.
We used to take a Triang Floor layout on Holiday which was laid on the floor or patio. Bit back breaking to keep kneeling down and crawling around and Premier Inn get a bit funny when you glue the ballast down.
The garden line is at ground level about 36" above the path at one point, 12" underground at another. Looks great viewed from the bedroom window.
What ever height has issues, if the top is easy to get at the wiring underneath may be difficult.
I like the US style multiple level layouts, some with helix, some constant gradient,worst / best of all worlds especially those with hidden sidings / staging on the top level overhead and a realistic Port/ Harbour on the lowest level. My Harbour has hidden sidings under and is at the top of a gradient...
Wheel chair access is an issue, not sure how real an issue, wheel chair users can't get in my loft anyway.
Edited by DavidCBroad, 13 March 2018 - 14:27 .