Deciding What is "Available Space" for a Model Railroad Layout

Designing an O Gauge Model Railroad Layout for a Spare Bedroom

What is the "available" space in a room?

Spare Bedroom will be Model Railroad Layout site.

After deliberating between the two O gauge model railroad locations: garage or spare bedroom (discussed on Page 1), I decided to build it in the spare bedroom, which is 14′ 10” by 11′ 6” .

So, now that the location is chosen, how big of an O gauge model railroad layout can we cram into it? 
My first inclination was to completely fill the area with benchwork. The advantages of this would be that I could not only use 72” curves, but even broad 96” or 120” curves on the outer main line.

I finally settled on a more realistic plan. Read more on Page 2 of the O Gauge Model Railroad Layout Project.