Hi Barrie,
The layout is being built in the loft, and the area you have mentioned is the top of the loft ladder.
The approximate size is 4.8M x 3.7M.
We converted the loft especially for the layout, (as i wasnt prepared to loose the spare bedroom), and has taken 12 months so far, we have laid the baseboards, and are in the process of laying track.
The layout plan was drawn using AnyRail so the track is scaled, the loft ladder isnt !
Allison