“I cut out something resembling a fire place and made a roof from a 6mm thick piece of floor insulation board (polystyrene foam)”
I was looking at this myself, is it very bendy?
I wanted to make some stone floor areas by inscribing the detail into the foam.
However I am concerned it is not very rigid?
Would it glue nicely to a plasticard sheet underneath do you think to keep it from bending/warping?