Mark Boyce posted:
I setup a ‘temporary ‘ Christmas layout on 2” foam supported by about 20” centers. It stayed up for 3 years without a sag. Now I’m building permanent on 1/2” wood and Homasote for track, but I don’t mind building a town on foam .
Mark, I did a test of 12" overhang with a train parked for about 6 months, with no discernable deformation of the foam. I am planning on 16" centers, but with 2"x2" supporting the foam at each center, so really about a 14" span between supports.