Layout compromises

[ChrisGreaves]

... built a lightweight box on the flat roof outside his layout room, so that all the 'run round' lines don't eat scenic layout space.

OK.
I'm a man.
I can compromise.

How about a garden layout as close to 1:1 scale as possible, and in that layout a house with a flat roof and a T-scale model railway running around that roof?

That would start to look realistic.
Cheers, Chris